Militants have seized a number of districts across Afghanistan, and fighting is likely to intensify as warmer weather sets in.

A roadside bomb has killed at least nine Afghan security forces during an ongoing operation against the Taliban in the northern Balkh province, an Afghan official said on Sunday.

Munir Ahmad Farhad, spokesman for the provincial governor, said several other forces were wounded the night before in the Chimtal district. He said five insurgents have been killed and dozens wounded.

Afghan forces have struggled to combat the Taliban since the U.S. and NATO formally concluded their combat mission more than two years ago and shifted to a support and counterterrorism mission. The Taliban have seized a number of districts across the country, and the fighting is expected to intensify as warmer weather sets in.

U.S. soldier killed in Nangarhar

The U.S. military had earlier said an American soldier was killed in combat in the eastern Nangarhar province. The soldier was a member of U.S. special operations forces helping Afghan forces battle a local Islamic State affiliate in the Achin district, the statement said.

The Islamic State group has a growing presence in eastern Afghanistan, where it has battled both Afghan forces and the much larger and more powerful Taliban.