A senior police officer, who did not wish to be named, told Dawn that it was an act of terrorism.

He said personnel from the Bomb Disposal Squad had found the lever of the grenade [at the crime scene] and confirmed that a Russian-made device had been used in the attack.

The attack took place in Baldia area.

“We are investigating the incident from different angles to ascertain whether the perpetrators were terrorists from some ethnic group or an extremist group,” said the official to the news channel.

Local police and the Counter-Terrorism Department have started investigating the incident.

Karachi South Zone DIG Javed Akbar Riaz told Dawn that the truck was carrying 20 to 25 people who were returning from a marriage ceremony.