Taliban militants captured a district in Afghanistan's Ghazni province near the provincial capital early on Thursday and killed more than a dozen people including the district's governor, a police official said.
Ghazni's Khawaja Omari district was considered one of the province's safest districts.
The militants killed district governor Ali Dost Shams, his bodyguards, seven police officers and five government intelligence agents, said Ramazan Ali Mohseni, deputy police chief in Ghazni.
The Taliban then torched the district headquarters, he said.
Taliban spokesman Zabihullah Mujahid said in a statement 20 police officers were killed in the attack.
The fall of Khawaja Omari to the Taliban extends their territory closer to the provincial capital, also called Ghazni, a city of 150,000 people 150 km (95 miles) southwest of the Afghan capital, Kabul.
Fighting in Afghanistan traditionally increases in the spring when warmer weather melts snow blocking mountain passes, increasing the mobility of the insurgents.
The Taliban usually announce the launch of a spring offensive in April.