A group of suicide bombers have attacked a U.S. base on the Afghanistan-Pakistan border, on Monday, triggering multiple explosions and a gun battle, an Afghan official told Associated Press, or AP.

Ahmad Zia Abdulzai, a spokesman for the governor of Afghanistan's Nangarhar province, said that a group of heavily-armed militants attacked the base in the Torkham area, which lies about 35 miles west of the Pakistani city of Peshawar.

Explosions were heard from the site and U.S. forces were engaged in a gun fight with the insurgents, AP reported, citing Abdulzai. NATO helicopters were flying over the U.S. base and there were no immediate reports of casualties, he told AP.

The Taliban claimed responsibility for the attack on the base and an organization spokesman, Zabiullah Mujahid, in an emailed statement to AP, claimed that its fighters staged the Monday morning attack and that they were successful in destroying several tanks during the attack.

NATO confirmed “a series of explosions” in the area but did not say who was behind the attack and said there were no casualties from NATO. The highway between the city of Jalalabad and Torkham, a key route for NATO supply trucks, has been closed. 

Militants from both Pakistan and Afghanistan have targeted the supply route in the past. Taliban and other insurgent groups in Afghanistan have escalated their attacks in recent months, as foreign troops have reduced their presence in the country ahead of their planned withdrawal by the end of 2014.

On Sunday, local residents had found bullet-ridden bodies of seven Afghan soldiers in Andar district of Ghazni province, in eastern Afghanistan. The slain soldiers hailed from the country's northern provinces and were abducted by militants at different times, Dawn, a Pakistani newspaper, reported.