Nine American soldiers were killed and 15 were wounded on Sunday, officials said, in what appears to be the deadliest attack on U.S. forces in Afghanistan in years.

The soldiers were killed in a multi-pronged insurgent attack, NATO'S International Security Assistance Force said in a statement. It happened around 4:30 a.m. on a remote American base in the province of Kunar -- a mountainous region in eastern Afghanistan that borders Pakistan.

Militants fired machine guns and rocket-propelled grenades from nearby homes and a mosque, said officials.

Nine U.S. troops were killed in the attack, a western official said on condition of anonymity because he was not authorized to release the troops' nationalities. NATO did confirm that nine of its soldiers died in the attack and 15 were wounded. Four Afghan soldiers were also wounded, NATO said.

"Although no final assessment has been made, it is believed insurgents suffered heavy casualties during several hours of fighting," NATO said in a statement.

The attack appeared to be the deadliest for U.S. troops in Afghanistan since June 2005, when 16 U.S. troops were killed when their helicopter was shot down by a rocket-propelled grenade. That attack also occurred in Kunar province.

Word of the attack coincides with news of a separate deadly suicide bombing attack on civilians in southern Afghanistan. Twenty-four people were killed in that attack when a suicide bomber on a motorcycle blew himself up next to a police patrol.

The dead included five police officers and 19 civilians, some of them boys who happened to be selling goods on the street. More than 30 others were injured.

There was also word on Sunday that a top Afghan politician was also kidnapped. Logar province Police Chief Gen. Mohammad Mustafa said gunmen took away parliament member Abdul Wali and his driver.

The latest attacks follow a series of bombings this month. Just Monday, 55 civilians were killed in a bomb attack in Kabul on the Indian Embassy.

According to Associated Press figures, More than 2,300 people have died in insurgency-related violence this year. Many of the dead include militants.

With files from The Associated Press