Islamabad: At least two policemen were killed on Monday when a suicide bomber blew himself up in northwest Pakistan's Swat valley, the officials said.

"The suicide attacker was trying to sneak into the Mangora police lines by climbing over a wall, but he blew himself up as soon as the officers on duty challenged him," said the area police chief Akhtar Ali Shah.

Five policemen were injured in the bombing, he added.

The Swat district that lies in country's North-West Frontier Province has seen a rise in suicide bombings since the Pakistan army launched a major offensive to flush out the pro-Taliban militants from the region.

Dozens of security officials and civilians have died in the series of bombings, which include a suicide attack on the funeral of a police officer Feb 29 that left more than 40 people dead and about 80 injured.

Source : IANS