A policeman in southern Afghanistan killed seven of his fellow officers, first poisoning them and then shooting them, a government spokesman said Tuesday, DPA reported.
The incident took place at a checkpoint in Lashkargah, the capital of Helmand province, said Daud Ahmadi, spokesman for the provincial governor.
The suspect fled after stealing ammunition and remained at large, Ahmadi said.
Taliban spokesman Qari Yousuf Ahmadi said the victims were killed by a Taliban sleeper agent.
Lashkargah is one of seven areas where foreign troops are to hand over security responsibility to their Afghan counterparts this week.
In neighbouring Kandahar province, gunmen killed a local tribal leader in the city late Monday, said Sher Shah Yousufzai, deputy police chief in the province's capital, also called Kandahar.
NATO officials claimed gains in southern provinces in the past year, but insurgent attacks have increased in recent weeks. Last week, President Hamid Karzai's half-brother, a southern political leader, was shot dead by one of his bodyguards.