Taliban militants have attacked a police station in southern Afghanistan, killing three officers and abducting 19 people working for a land mine clearance project in the country's east.

The attacks came amid spiralling violence as Taliban insurgents and the US-trained Afghan government forces vie for control after the end of the Nato combat mission last year saw most foreign troops withdraw.

Gunmen wearing police uniform entered a police station in Helmand province and opened fire, killing three police.

The attack took place in Lashkar Gah, the provincial capital. Afghanistan's armed forces launched a major offensive against Taliban insurgents in Helmand this spring.

The kidnap of the de-miners in the eastern province of Paktia was the latest in a series and came days after four abducted ethnic Hazara men were killed by their captors.

Abdul Wali Sahi, deputy governor of Paktia, said the Taliban abducted the de-miners while they were surveying an area on the outskirts of Gardez, the provincial capital.