KARACHI: The Tehrik-i-Taliban Pakistan (TTP) claimed responsibility Thursday for an explosion targeting a police bus near Razzaqabad police training college in Karachi's Shah Latif Town in which 13 policemen were killed and 47 others, including civilians, were wounded, DawnNews reported.

The attack came early in the morning. “Apparently an explosive-laden car hit the police bus transporting officials for security duty,” Muhammad Iqbal, a senior police official, told AFP.

Rescue teams reached the site of attack whereas the victims were shifted to Jinnah Hospital and a private hospital nearby in the locality.

Doctor Seemin Jamali at Karachi's Jinnah hospital confirmed that there were at least 11 dead. At least 47 wounded officers were hospitalised, 10 of whom were in critical condition, she said.

Speaking to Dawn.com, Pakistani Taliban spokesman Shahidullah Shahid claimed responsibility for the attack and said it was a revenge attack for killing militants.

He said TTP workers were victims to targeted killings in Mardan, Swabi and Peshawar, adding that the attack was in response to that.

“Our defensive war will continue until an agreement is reached on a ceasefire” between negotiation teams representing the government and the Taliban, he told AFP.

SSP 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.

However a CID official refuted the claim that the bombing was carried out by a suicide attacker and said that no body parts were found from the site to support the notion. The official added that blast appeared to have been carried out using a remote-controlled detonator.

According to initial reports, 25 to 30 kilograms of explosives were used in the attack.

Police said that more than 50 officers were boarding the vehicle at the time of attack, which occurred in the eastern district of Karachi close to the national highway.

“Around 50-55 policemen were boarding the bus and going somewhere for duty from their training centre,” Iqbal said adding that police suspect it was a suicide attack.

There was no immediate claim of responsibility for the attack.

The rear portion of the targeted bus was completely destroyed in the explosion.

Moreover, additional contingents of police, Rangers and the Bomb Disposal Squad (BDS) reached the spot and cordoned off the area as a probe into the incident went underway.

The intensive blast was heard in a radius of two kilometres.

“We are investigating this attack from all angles and who had the most to lose by the forces' actions and want harm upon them. But the forces will not be demoralised and will work more aggressively,” Sharjeel Memon, minister for information in the southern province of Sindh which includes Karachi, told reporters.

Moreover, President Mamnoon Hussain, Balochistan Chief Minister Abdul Malik Baloch, Muttahida Qaumi Movement chief Altaf Hussain and the Majlis Wahdat-i-Muslimeen (MWM) issued statements in condemnation of the attack .