KARACHI: A powerful car bomb attack on a police bus on Thursday in Pakistan's commercial hub of Karachi, killed at least 11 policemen and wounded 47 others, officials said.
The attack came as Pakistan has been locked into negotiations with the Taliban aimed at ending a seven-year insurgency, with the level of violence in the country showing no signs of abating since talks began at the end of last month.
Munir Sheikh, a senior police official, told reporters the attack took place in the early morning.
"Apparently it was a suicide car attack as an explosive-laden car hit the police bus transporting officials. So far 11 policemen have died."
Another official, Farooq Awan who heads a special investigative unit, said the bus was making a U-turn after leaving a training centre when a small van struck it.
Doctor Semi Jamali at Karachi's Jinnah hospital confirmed that they had received 11 bodies.
At least 47 wounded officers were hospitalised, 10 of whom were in critical condition, she said.
Police said that more than 50 officers were on board the vehicle at the time of attack, which occurred in the eastern district of Karachi close to the national highway.
There was no immediate claim of responsibility for the attack, which was the 11th since Prime Minister Nawaz Sharif announced talks on January 29 saying he wants to "give peace another chance".
The Pakistani Taliban have claimed several attacks on the security forces including the assassination of Karachi police senior official Chaudhry Aslam earlier this year.
Karachi, a city of 18 million people which contributes 42 percent of Pakistan's GDP, has also been plagued by sectarian, ethnic and political violence for years.
Pakistan has endured a bloody start to the year with 114 people killed in attacks in January, according to an AFP tally.
More than 60 people have been killed since Sharif announced the talks. (AFP)