KABUL, Afghanistan — A series of Taliban attacks over the past two days have left 9 Afghan police officers dead and 14 missing, in the latest sign that insurgents are pressing their fight against security forces as the annual fighting season gets under way with the spring thaw.

In the deadliest episode, insurgents attacked a police post in the southern province of Helmand late Monday, killing four police officers and two civilians, said Col. Muhammad Nabi Elham, the provincial police chief. Three other police officers were missing, along with a police Toyota Ranger pickup truck and weapons kept at the post.

Mr. Elham initially said the officers at the post may have been poisoned but later backed off that claim. A Taliban spokesman, Qari Yousaf Ahmadi, said the insurgents carried out the attack and lost one of their own in the fighting on Monday.

Also on Monday night, insurgents attacked a checkpoint in Badakhshan Province, killing three police officers, said Abdul Marouf Rasekh, a spokesman for the provincial government, according to The Associated Press.