Punjab provincial law minister Rana Sanaullah said the attack appears to be "an act of terrorism."
At least four people have been killed in a blast which appeared to have been an attack targeting a census team in Pakistan's eastern city of Lahore Wednesday, officials said.
Security officials had cordoned off the area on Bedian Road in the bustling capital of Punjab province after the blast, which rescue officials said occurred just before 8:00 am local time.
"It appears to have been an act of terrorism," Punjab provincial law minister Rana Sanaullah said in televised comments, adding that two soldiers and two civilians had been killed.
Rescue officials and police confirmed the toll, with a police official telling AFP the census team had been the target of the attack.
Teams of enumerators backed by the military and security forces are carrying out Pakistan's first census in almost two decades, an enormous and highly charged task that could redraw Pakistan's political map one year before national parliamentary elections.
"Four people are dead so far and at least 18 injured, who were shifted to hospital," said rescue spokeswoman Deeba Shahnaz. The police official said at least 10 people had been wounded.
Shahnaz initially described the incident as a gas cylinder explosion, but said the operation was ongoing.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)