ISLAMABAD, June 4 (Reuters) - Pakistan on Monday strongly condemned a jump in U.S. drone strikes on its territory, using language that could increase tension between strategic allies already in dispute over military supply routes for NATO that Pakistan has closed.

Three drone strikes in as many days on suspected militants have killed 27 people, Pakistani intelligence officials say.

The foreign ministry called the attacks "illegal" and said they violated the South Asian country's sovereignty.

Washington and Islamabad are deadlocked in negotiations over the re-opening of overland supply routes to NATO forces in Afghanistan.

Islamabad blocked the supply routes in November after 24 Pakistani soldiers were killed by cross-border "friendly fire" from NATO aircraft.

The supply lines are considered vital to the planned withdrawal of most foreign combat troops from Afghanistan before the end of 2014.

The Pakistan government says the CIA drone campaign fuels anti-American sentiment in the country, and is counterproductive because of the collateral damage - civilian deaths - it causes.

U.S. officials say such strikes by the remotely piloted aircraft are a highly effective way of attackling militants and are an important weapon in the war against militancy. (Reporting by Qasim Nauman; Editing by Michael Georgy and Tim Pearce)

Also on HuffPost:

TYPES OF DRONES:
Loading Slideshow...
  • Boeing Phantom Ray

    <strong>Type</strong>: Military (U.S.) <strong>Description</strong>: Boeing's stealth Phantom Ray took to the skies for the <a href="http://www.boeing.com/Features/2011/05/bds_phantom_ray_first_flight_05_04_11.html" target="_hplink">first time in April 2011</a>. According to Boeing, the <a href="http://www.boeing.com/advertising/bma/unmanned/unmanned_05.html" target="_hplink">Phantom Ray can perform missions</a> such as intelligence, surveillance and reconnaissance, suppression of enemy air defenses, and electronic attack. <strong>Potential Deployment</strong>: Unknown. This is a "demonstrator" so there will likely be a future variation of the Ray.

  • General Atomics Predator Avenger

    <strong>Type</strong>: Military (U.S.) <strong>Description</strong>: General Atomics Aeronautical Systems <a href="http://www.ga-asi.com/products/aircraft/predator_c.php" target="_hplink">Predator Avenger C</a> is a beast. According to the two-page brochure, the PAC is a "Next-Generation Multi-mission ISR and Strike Aircraft" and successor for the Predator B that can be stacked with a multitude of weaponry. <strong>Deployment</strong>: There is one <a href="http://www.aviationweek.com/aw/generic/story.jsp?topicName=unmanned&id=news/awst/2011/12/19/AW_12_19_2011_p25-406500.xml&headline=USAF Plans Larger, More Capable Predator&channel=&from=topicalreports" target="_hplink">demonstration craft currently in Afghanistan</a>.

  • SOCOM Mini Drone Of Doom

    <strong>Type</strong>: Military (U.S.) <strong>Description</strong>: Yo dawg, I heard you like drones so I <a href="http://www.wired.com/dangerroom/2011/10/socom-warhead-drones/" target="_hplink">put a drone in your drone</a>. One small deadly warhead-equipped mini-drone stuffed into another, to be launched from the main drone and remotely aimed at a target. <strong> Potential Deployment</strong>: This <a href="http://defensenewsstand.com/NewsStand-General/The-INSIDER-Free-Article/socom-could-have-warhead-equipped-micro-uav-by-spring-2012/menu-id-720.html" target="_hplink">warhead-equiped micro-UAV</a> could be flown by SOCOM in the skies by spring 2012.

  • Suicide Switchblade

    <strong>Type</strong>: Military (USA) <strong>Description</strong>: <a href="http://www.avinc.com/uas/adc/switchblade/" target="_hplink">AeroVironment's Switchblade</a> is meant to be a portable, rapid deployment, beyond line-of-sight, "loitering munition" that is a "magic bullet." A bit of advice, AeroVironment: Don't describe a remote-controlled bomb as a "loitering munition" that you call "Switchblade," as it conjures up images of 1950's-style greasers loitering on street corners, flipping open switchblades idly as they wait for their favorite gals. Luckily, greasers won't be in charge of flying Switchblades. They're to be controlled by infantry and <a href="http://www.defensenews.com/story.php?i=7982421&&s=TOP" target="_hplink">according to the AeroVironment</a>, "Flying quietly at high speed the Switchblade delivers its onboard explosive payload with precision while minimizing collateral damage." <strong>Potential Deployment</strong>: Undisclosed.

  • Nano Hummingbird

    <strong>Type</strong>: Surveillance (USA, DARPA Funded) <strong>Description</strong>: AeroVironment is at it again. In partnership with DARPA, they've actually managed to build a human mechanically engineered version of one of nature's most amazing flying machines: the hummingbird. The <a href="http://www.avinc.com/media_gallery/" target="_hplink">Nano Hummingbird</a> is a perfect bid for James Bond-esque style spy shenanigans. Once these hit the field, we'll never look at hummingbirds the same way. "Stop looking at me! That bird is following me!" <strong>Potential Deployment</strong>: Within five years.

  • Army A160 Hummingbird Drone

    <strong>Type</strong>: Military (U.S. Army) <strong>Description</strong>: Though the military's <a href="http://www.huffingtonpost.com/2011/12/30/us-army-hummingbird-a160-helicopter-drone_n_1176763.html?ref=technology" target="_hplink">A160 Hummingbird drone</a> doesn't resemble an actual hummingbird so much as AeroVironment's take, it is <a href="http://www.salon.com/2011/12/06/nprs_domestic_drone_commercial/" target="_hplink">raising just as many alarms</a> because of its potential to be deployed on the U.S. home front. <strong>Potential Deployment</strong>: May or June 2012, Afghanistan

  • Firescout

    <strong>Type</strong>: Military (U.S. Navy) <strong>Description</strong>: Northrop Grumman <a href="http://www.as.northropgrumman.com/products/mq8bfirescout_navy/index.html" target="_hplink">describes the Firescout</a> as a "Transformational Fire Scout Vertical Takeoff and Landing Tactical Unmanned Aerial Vehicle system provides unprecedented situation awareness and precision targeting support for U.S. Armed Forces of the future. The MQ-8B Fire Scout has the ability to autonomously take off and land on any aviation-capable warship and at prepared and unprepared landing zones in proximity to the soldier in contact." <strong>Potential Deployment</strong>: <a href="http://www.irconnect.com/noc/press/pages/news_releases.html?d=237497" target="_hplink">March 2013</a>

  • Euro Hawk

    <strong>Type</strong>: Military (German Ministry of Defense, purchased from Northrop Grumman) <strong>Description</strong>: NG touts its <a href="http://www.as.northropgrumman.com/products/euro_hawk/index.html" target="_hplink">Euro Hawk</a>, built for German Ministry of Defense, as having a "wingspan larger than a commercial airliner, endurance of more than 30 hours and a maximum altitude of more than 60,000 feet, EURO HAWK is an interoperable, modular and cost-effective replacement to the aging fleet of manned Breguet Atlantic aircraft, which have been in service since 1972 and will be retired in 2010." <strong>Potential Deployment</strong>: 2015, 2016 (<a href="http://www.as.northropgrumman.com/products/euro_hawk/assets/SIGINT_NewsRelease_101211.pdf" target="_hplink">PDF</a>)

  • X-47B

    <strong>Type</strong>: Military (U.S. Navy) <strong>Description</strong>: A carrier-based combat drone, <a href="http://www.as.northropgrumman.com/products/nucasx47b/index.html" target="_hplink">Northrop Grumman's futuristic X-47B</a> flew in its cruise configuration <a href="http://www.irconnect.com/noc/press/pages/news_releases.html?d=239278" target="_hplink">for the first time</a> on November 22, 2011. It can land with precision on the deck of a moving aircraft carrier, and features twin weapons payload bays that hold up to 4,500 lbs. (<a href="http://www.as.northropgrumman.com/products/nucasx47b/assets/X-47B_Navy_UCAS_FactSheet.pdf" target="_hplink">PDF</a>). <strong>Potential Deployment</strong>: <a href="http://www.wired.com/dangerroom/2011/11/navy-killer-drone-refuel/" target="_hplink">2018</a>

  • Taranis

    <strong>Type</strong>: Military (British) <strong>Description</strong>: BAE System's Taranis (<a href="http://www.baesystems.com/BAEProd/groups/public/documents/bae_publication/bae_pdf_taranis_fact_sheet.pdf" target="_hplink">PDF</a>) is aiming to "Push the boundaries by providing advancements in low observability capability and autonomous mission systems operations demonstrating the feasibility and utility of UAVs." Such a statement starts to push the idea of fully autonomous flight from science fiction into science fact, though we're still a long way off from having an actual real debate on fully autonomous drones fighting our battles and flying our skies. Potential Deployment: TBD, test flights have been delayed to 2012.

  • Boeing Phantom Eye

    <strong>Type</strong>: Communications <strong>Description</strong>: Boeing's hydrogen-powered <a href="http://www.boeing.com/Features/2010/07/bds_feat_phantom_eye_07_12_10.html" target="_hplink">Phantom Eye</a> is a High Altitude Long Duration Craft designed to fly at <a href="http://www.boeing.com/Features/2011/11/bds_phantom_eye_11_16_11.html" target="_hplink">65,000 feet for up to four days</a>. <strong>Potential Deployment</strong>: Unknown

  • DARPA Vulture

    <strong>Type</strong>: Intelligence, Surveillance, and Reconnaissance (ISR) <strong>Description</strong>: <a href="http://www.darpa.mil/Our_Work/TTO/Programs/Vulture.aspx" target="_hplink">DARPA's description</a> says the "Vulture technology enables a re-taskable, persistent pseudo-satellite capability, in an aircraft package." Basically, DARPA is attempting to develop a super long duration craft capable of five year continuous flight. Think about that - the Vulture is intended to fly for up to five years continuously. If it were to launch this year it would be in the air for two Olympics. <strong>Potential Deployment</strong>: Unknown

  • AVIATR: Drone To Fly Saturn's Moon

    <strong>Type</strong>: Government Funded Space Exploration <strong>Description</strong>: While the proposal probably won't go through for this mission, this is an aerial drone we can really get behind. <a href="http://www.huffingtonpost.com/2012/01/04/aviatr-probe-proposed-mission-titan_n_1184028.html" target="_hplink">AVIATR</a> would be a long distance drone that would fly the skies of Saturn's moon Titan. <strong>Potential Deployment</strong>: Beyond 2020

  • Japan Defense Ministry Ball Drone

    <strong>Type</strong>: Surveillance (Japan) <strong>Description</strong>: Techcrunch <a href="http://techcrunch.com/2011/10/25/video-japans-defense-ministry-develops-awesome-ball-shaped-drone/" target="_hplink">tells us</a> that the drone can "stand still in mid-air, fly vertically and horizontally through narrow spaces at up to 60km/h, and (which is very cool) keep on moving when it hits the ground or a wall. Thanks to three gyro sensors in its body, the machine can keep also flying even if it's hit by an obstacle." And all for only $1,400. <strong>Potential Deployment</strong>: Undisclosed