A rocket strike on a U.S. air base in Afghanistan has damaged the aircraft that was being used by General Martin Dempsey, the top uniformed U.S. military officer, who was making a visit to Kabul.

Taliban spokesman Zabiullah Mujahid claimed that Taliban fighters carried out the attack.

Officials said Dempsey, the chairman of the U.S. Joint Chiefs of Staff, was not onboard the C-17 transport aircraft and was not injured.

Officials said the aircraft was only being used temporarily by Dempsey and his staff.

The rocket strike also damaged a nearby helicopter.

Officials said Dempsey flew out of Bagram air base on another plane.

Dempsey's spokesman, Colonel Dave Lapan, said two insurgent rockets struck Bagram overnight, with one causing damage to Dempsey's C-17.

Officials said no danger was ever posed to Dempsey or his staff, who were asleep in their quarters at the time of the incident.

NATO spokesman Colonel Thomas Collins called the rocket strike a "lucky shot."

Bagram, located outside Kabul, is occasionally targeted with rockets and mortar shells fired by insurgents from surrounding hills and fields.

NATO officials say the militants are not believed to have the capability to reliably strike with accuracy at targets at the base, which is usually where visiting foreign dignitaries arrive for visits to Afghanistan.

In May 2010, militants launched a coordinated assault on Bagram, injuring several NATO troops.

Two U.S. soldiers were killed in a similar attack in June 2009.

Dempsey had arrived in Afghanistan on August 20 for talks with Afghan and NATO coalition leaders about a growing number of attacks against NATO soldiers by Afghan security personnel.

The attacks have killed 10 U.S. soldiers in the past two weeks.

On August 20, Dempsey met with Afghan military leaders in Kabul. He said that "for the first time" his Afghan counterparts are as concerned as Washington is about the so-called "insider" attacks.

President Barack Obama has expressed "deep concern" about the killings. Obama said he would reach out to Afghan President Hamid Karzai about the situation.

NATO's 130,000 troops in Afghanistan are due to withdraw by the end of 2014 as the alliance seeks to draw down the conflict, which is now in its 11th year. Dempsey said the insider attacks are not expected to alter the withdrawal timetable.

Analysts say the growing number of attacks is likely to intensify pressure on the leaders of NATO member nations to move toward an early exit from what has become an increasingly unpopular conflict among many of their citizens.

With reporting by AFP, AP, and Reuters