President Barack Obama on Friday ordered flags at government buildings around the country to be flown at half staff in tribute to victims of the deadly mass shooting in Aurora, Colorado.

Early Friday morning, 24-year-old James Eagan Holmes allegedly opened fire on theater-goers attending a midnight premiere of the summer blockbuster "The Dark Knight Rises," killing at least 12 and wounding 59, according to police.

Obama addressed the incident early Friday, saying that he and the first lady were shocked by the "horrific and tragic" events.

At a campaign event later in the day, he gave further comments.

"We're going to stand by our neighbors in Colorado during this extraordinarily difficult time. Such violence, such evil is senseless; it's beyond reason." Obama said. "What matters at the end of the day is not the small things; it is not the trivial things ... Ultimately it is how we choose to treat one another and how we love one another."

He added, "We do know what makes life worth living. People in Aurora loved and were loved."

The president's proclamation is set to go into effect immediately and last until sunset of July 25.

Read the entire proclamation below:

As a mark of respect for the victims of the senseless acts of violence perpetrated on July 20, 2012, in Aurora, Colorado, by the authority vested in me as President of the United States by the Constitution and the laws of the United States of America, I hereby order that the flag of the United States shall be flown at half-staff at the White House and upon all public buildings and grounds, at all military posts and naval stations, and on all naval vessels of the Federal Government in the District of Columbia and throughout the United States and its Territories and possessions until sunset, July 25, 2012. I also direct that the flag shall be flown at half-staff for the same length of time at all United States embassies, legations, consular offices, and other facilities abroad, including all military facilities and naval vessels and stations.

IN WITNESS WHEREOF, I have hereunto set my hand this twentieth day of July, in the year of our Lord two thousand twelve, and of the Independence of the United States of America the two hundred and thirty-seventh.

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  • Barack Obama

    "Michelle and I are shocked and saddened by the horrific and tragic shooting in Colorado," President Obama said in a statement. "Federal and local law enforcement are still responding, and my Administration will do everything that we can to support the people of Aurora in this extraordinarily difficult time. We are committed to bringing whoever was responsible to justice, ensuring the safety of our people, and caring for those who have been wounded. As we do when confronted by moments of darkness and challenge, we must now come together as one American family. All of us must have the people of Aurora in our thoughts and prayers as they confront the loss of family, friends, and neighbors, and we must stand together with them in the challenging hours and days to come."

  • Mitt Romney

    "Ann and I are deeply saddened by the news of the senseless violence that took the lives of 15 people in Colorado and injured dozens more," Mitt Romney said in a statement. "We are praying for the families and loved ones of the victims during this time of deep shock and immense grief. We expect that the person responsible for this terrible crime will be quickly brought to justice."

  • Michael Bloomberg

  • Sen. Robert Menendez

  • Louie Gohmert

  • Scott P. Brown

  • Jay Rockefeller

  • Reince Priebus

  • Jim Himes

  • Charles Rangel

  • Kevin McCarthy

  • Nancy Pelosi

  • Ed Perlmutter

  • Mark Udall

  • Speaker John Boehner

  • David Vitter

  • John McCain

  • Sherrod Brown

  • Allen West

  • Senator John Thune

  • Kelly Ayotte

  • Michael Bennet

    "This was horrible, senseless and abhorrent act," Sen. Michael Bennet (D-Co.) said in a statement. "My family and I are shocked and deeply saddened this morning and our hearts are with the victims and their families. My staff and I are in contact with and offering our support to law enforcement and medical officials as they respond to the shooting."

  • "This is not only an act of extreme violence, it is also an act of depravity," Colorado Gov. John Hickenlooper (D) said.

  • Mike Huckabee

    "Heartfelt prayers for the victims in Aurora, Colorado and all those impacted by this terrible tragedy," Mike Huckabee said in a statement on his Facebook page.

  • Rob Portman

  • JohnCornyn

  • Tim Kaine

    "I am heartbroken and shocked by the horrific act of violence in Colorado," Tim Kaine said in a statement. "The thoughts of Anne and I are with the families who have lost loved ones in this senseless tragedy. We continue to pray for the recovery of those who have been wounded, and we offer our support to Governor Hickenlooper and the entire community of Aurora as they heal."

  • Mike Coffman

  • Nikki Haley

    ‎"Michael Haley and I have the victims and their families of the Colorado massacre in our thoughts," South Carolina Gov. Nikki Haley (R) said in a statement on Facebook. "Please join us in prayer for all those effected by this horrible senseless tragedy."

  • "I join in mourning the tragic loss of life in Colorado this morning. The families of the victims, the many injured, and all those in Aurora are in my thoughts and in my prayers," House Democratic Whip Steny Hoyer said in a statement Friday. "It is in times like these that Americans have always rallied together as one community and one family, and we do so again today. I commend the heroism of our first responders from local and federal law enforcement and area hospitals, who have done an outstanding job in the face of great difficulty. "As the people of Aurora find themselves facing their darkest hour, I hope they find comfort knowing that the memories of the lost will never fade, their community will remain strong, and that the nation stands united alongside them as their process of healing begins."

  • Mitch McConnell

    "Elaine and I are heartbroken by the shootings in Aurora," Senate Minority Leader Mitch McConnell said Friday in a statement. "This senseless massacre of so many innocent people gathered with friends and family in a movie theater reminds us not only of the great evil that exists in the hearts of some, but of the great and precious gift of life. I join all Americans today in prayer for the victims, their families and friends, and the wider Aurora community, and in heartfelt thanks to all the first responders who quickly responded at great risk to themselves. It is in moments like this that Americans have always drawn closer together and shown their great compassion and generosity to those touched by tragedy and loss. We hope that in the midst of the horror in Aurora, these qualities shine through once again and reach those who are suffering most. America is at prayer today for all who are affected by this tragedy."

  • MicheleBachmann

  • Chuck Schumer

  • Rep. Diana DeGette

  • Harry Reid

    "The shooting in the Aurora movie theater is a national tragedy, and the victims of this cruel and violent act are in my thoughts," Senate Majority Leader Harry Reid said in a statement Friday. "Innocent people suffered a heartbreaking loss, but the victims and their families are not alone. Today, Americans take time to reflect on the value of life and the things that are most important to us, and mourn for those who lost what is most important to them. Everyone affected by this violent act will be in our hearts today, and for a long time to come."

  • Carolyn McCarthy

    "The horrific nightmare of a mass shooting on innocent civilians in a crowded public place has, sadly, come true once again," said Rep. Carolyn McCarthy (D-N.Y.), whose family was affected by a mass shooting on the Long Island Railroad before she was elected to Congress, in a statement Friday. "I mourn alongside the people of Aurora for the many killed and injured and the countless family and friends whose lives, as a result of the consequences of this event, will be negatively affected for decades to come. The shooter should be brought to justice and prosecuted to the fullest extent of the law. But we as a nation should also not continue to ignore avenues to prevent tragedies like this from happening in the future."

  • Senator Dick Durbin

  • Condoleezza Rice

  • Jeff Flake

  • "This is a terrible tragedy for the families of the victims, the city of Aurora and our entire nation," Democratic candidate for U.S. Senate in Massachusetts Elizabeth Warren said in a statement Friday. "This senseless violence has no place in our society. As a mother and grandmother, I am truly saddened that so many of the victims were so young. Bruce and I send our thoughts and prayers to the victims and their loved ones."

  • Gary Johnson

    "The shooting in Aurora is a senseless tragedy and a despicable act," said Libertarian Party presidential candidate and former New Mexico Gov. Gary Johnson in a statement Friday. "Our thoughts go out to the victims, their families, and to the entire community as they deal with the shock and grief today brings. "

  • Joe Biden

    "Jill and I were shocked to learn of the tragedy in Aurora, Colorado this morning," Vice President Joe Biden said in a statement Friday. "The reason this is so deeply felt by all Americans is that, but for the grace of God, the victims could have been any one of our children, in any one of our towns. It is every parent's worst nightmare to receive 'that phone call' and to sit by their child's bedside, praying. We know what it's like to wait and wonder and the helplessness a parent feels at this moment. Our hearts go out to each and every person who is suffering right now as a result of this terrible event. The prayers of an entire nation are with the victims and their families. We stand with the city of Aurora and the state of Colorado in mourning."

  • Newt Gingrich

  • Steve Israel

  • Mark Kelly

  • Gov. Buddy Roemer

  • Claire McCaskill

  • John Lewis

  • Rick Santorum

  • Sarah Palin

    "Todd's and my thoughts and prayers go out to the victims of the terrible tragedy in Colorado," Sarah Palin said Friday in a statement on Facebook. "Our family joins others in praying for everyone affected by the evil that inexplicably took innocent lives. We wish to remind all to hold loved ones tight."

  • ChuckGrassley