Suspected militants forced passengers to step out of three buses and shot dead at least 20 of them in an attack on Thursday in northwest Pakistan, officials said.

The officials said between at least a dozen armed men wearing army uniforms checked the identification cards of the passengers and then opened fire after learning they were Shiite.

Khalid Omarzai, chief administrator of Mansehra, told the AFP news agency that the militants checked the identity cards of passengers and then "opened fire."

"All are Shiites," said Omarzai.



This is the third such attack in this region. Two similar bus attacks in February and April of this year killed 27 Shiites. Police official Ali Sher said the gunmen in Thursday's attack had fled and a search had been launched.

According to Pakistani authorities, the attack occurred in the Mansehra district. The buses were traveling from Rawalpindi near Islamabad to Gilgit in the north.

Pakistan is a majority Sunni Muslim state, and the country has a long history of sectarian attacks by extremists on both sides.

Earlier on Thursday militants attacked an air force base in northern Pakistan, sparking a battle that killed at least nine, security officials said.

The clash broke out before dawn at the Kamra airbase in the Attock district of Punjab province when security forces intercepted the militants, said Group Captain Tariq Mahmood, an air force spokesman. The Taliban claimed responsibility for this attack and warned more would follow.

hc/mz (Reuters, afp, dpa)