A spokesman for the Ministry of Defense, Ghafoor Ahmad Jawed, said that reinforcements were being sent to try to recapture the base, and that the authorities were unsure of the number of casualties. Other Afghan officials gave divergent tallies. Abdul Hakim, the district governor of Poshti Koh, said 18 officers had been killed and 23 others taken prisoner. There were 48 officers in the battalion.

In another attack on Monday, the Taliban targeted a security outpost in the district of Khogyani, in Ghazni Province, killing at least 13 members of the Afghan security forces and wounding three others, according to Mohammad Arif Noori, the governor’s spokesman. “Six police officers and seven soldiers were among those killed,” he said. “It was a joint outpost of army and police which was built two days ago.”

Six Taliban fighters were also killed in the assault, and 10 others were wounded, he added.

Farah Province has been the scene of heavy fighting this year, with insurgents briefly overrunning its capital in May. Ghazni, too, has seen heavy fighting, with its capital nearly captured by the Taliban in August.

In Kandahar Province, 12 police officers were killed in a Taliban attack before dawn Monday on a police outpost in the district of Khakrez, according to Malim Mir Hamza, the district governor. Insurgents captured the outpost and seized all of the weapons and equipment there, he said.

In two other attacks in Kandahar on Monday, a total of five police officers were killed and seven others wounded when insurgents attacked security outposts in the districts of Maruf and Arghistan, according to Zia Durrani, the spokesman for the Afghan police in the province.

Kandahar, once a stronghold of the Taliban and the organization’s base, has been relatively quiet over the past year. But the insurgents killed the province’s powerful police chief, Gen. Abdul Raziq, in an insider attack last month.

In four smaller assaults on Monday, a total of at least nine members of the security forces were killed in the provinces of Zabul, in the south; Faryab and Sar-i-Pul in the north; and Badghis, in the northwest, local officials said.