Kabul, July 24 (Reuters) - Afghan security forces have foiled a plan by insurgents to attack a major international hotel in Kabul, intelligence officials said on Tuesday, blocking what would have been the second such attack in the capital in as many months.

Describing the plan as "major and aggressive", a spokesman for Afghanistan's National Directorate of Security (NDS) said the attack could have caused carnage, although he refused to give details.

"Terrorists planned to launch an attack on a five-star hotel. We avoided the assassination of scores of our people and the destruction of an important installation," said Shafiqullah Tahiri, the deputy spokesman for the NDS.

Investigations into the attack were continuing, he said.

Taliban gunmen in June stormed a small resort hotel and restaurant at Qargha lake, on Kabul's outskirts, taking hostages and killing 20 people with rocket-propelled grenades, suicide vests and assault rifles.

Afghan police and NATO-led international forces ended the attack after a 12-hour siege, but it again showed the ability of insurgents to stage high-profile raids even as NATO nations prepare to withdraw most of their combat troops by the end of 2014 and leave Afghans to lead the fight.

In April, Taliban fired rockets into the Star Hotel near President Hamid Karzai's presidential palace during an attack on the city's central business area, while in June 2011 insurgents attacked the Kabul Intercontinental Hotel, killing 19 people, including all eight attackers. (Editing by Rob Taylor)