KABUL (AP) – Taliban militants attacked government buildings in the southeastern city of Khost on Saturday with suicide bombers, AK-47 rifles and rocket-propelled grenades, officials said.

At least three suicide bombers blew themselves up during the attack, which began in the early afternoon and was ongoing, Defense Minister spokesman Gen. Mohammed Zahir Azimi said. Azimi said Afghan forces had surrounded the attackers and were firing on them.

Provincial council member Tajaly Khan Saber told The Associated Press that it was impossible to determine casualties because residents could not move about in the streets of Khost, site of a major U.S. military base, about 95 miles (150 kilometers) south of Kabul. It was not clear if U.S. troops were involved in the fighting Saturday.

Last May, 11 Taliban suicide bombers struck government buildings in Khost, killing 20 people and wounding three Americans.

On Tuesday, suspected Taliban militants armed with bombs, rifles and rocket-propelled grenades launched near-simultaneous assaults in Gardez, about 50 miles (80 kilometers) northwest of Khost, and in the eastern city of Jalalabad. Six Afghan police and intelligence officers and eight militants died in the two attacks.