A motorcycle bomb exploded at a roadside restaurant in northwest Pakistan, leaving at least two people killed and five others wounded on Thursday, police said.

A motorcycle bomb exploded at a roadside restaurant in northwest Pakistan, leaving at least two people killed and five others wounded on Thursday, police said.

The bomb was remotely detonated on the main highway between the towns of Kohat and Hangu in the northwestern province of Khyber Pakhtunkhwa, which is rife with Taliban and Al-Qaeda led militancy.

"The motorcycle was parked at a roadside restaurant 20 kilometres (12 miles) from Kohat city," Dilawar Khan Bangash, district police chief of Kohat, said.

"One person died at the spot, and another died while being moved to hospital," he added.

Hospital officials confirmed receiving one dead body and five injured.

Police said the motive for the attack was vague.

Early on Wednesday, a bomb targeting one of Pakistani President Asif Ali Zardari's senior personal security officers killed at least three people in Karachi.