LAHORE: At least six persons including four security officials were martyred in a suicide blast in passenger bus targeting security personnel and a census team in Lahore's Bedian Road on Wednesday morning, Aaj News reported. 

Following the blast, the van was set ablaze reportedly. The vehicle was carrying census stuff.

Police and rescue teams rushed to the scene. According to Rescue 1122, the injured have been shifted to the nearby hospitals. Security officials had cordoned off the area after the blast, which rescuers said occurred just before 8:00 am local time.

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 the country's political map one year before national parliamentary elections.

Rescue spokeswoman DeebaShahnaz and other officials initially described the incident as a gas cylinder explosion, but said an investigation was ongoing.

There was no immediate comment from the military, and no group immediately claimed responsibility for the attack.

Lahore has been on edge since a wave of violent attacks across Pakistan in February martyred 130 people and shook citizens emboldened by growing security.

The attacks included a bomb blast on February 13 which martyred 14 people in an assault claimed by Jamaat-ul-Ahrar (JuA).

Ten days later a fresh blast sent panic through the city when it claimed eight lives, though officials later said it was a gas leak, not an attack as initially feared.

Wednesday's explosion came days after at least 22 people were martyred and 57 wounded on March 31, when a car bomb tore through a market in Lahore in an attack that was also claimed by JuA.

February's assaults also included a suicide blast at a Sufi saint Lal Shahbaz Qalandar in the town of Sehwan which martyred 90 people.

PM Nawaz, President Mamnoon Hussain condemned the blast

President Mamnoon Hussain, Prime Minister Nawaz Sharif, Punjab Chief Minister Shahbaz Sharif, Interior Minister Chaudhry Nisar and Governor Punjab Rafique Rajwana have strongly condemned the Lahore blast.

The Prime Minister paid rich tributes to the personnel of Pakistan Army who were targeted while performing their duties during the national census.

He directed the authorities concerned to extend all requisite assistance to the provincial government.

Punjab CM Shahbaz Sharif has also extended sympathy and condolences to the bereaved families.

Chairman Pakistan Tehreek-i-Insaf (PTI) Imran Khan aslo strongly condemned terrorist attack.

In a statement issued here, he said enemies of Pakistan want to create chaos in the country. He stressed that more stringent measures should be adopted to defeat anti state elements and also those who were trying to de-stabilize the country. He expressed grief and sorrow over the loss of precious lives. He also prayed for the early recovery of injured.

"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.  -AFP/ AajNews