Policemen and people gather at the blast site in eastern Pakistan's Lahore, Feb. 13, 2017. (Xinhua/Sajjad)

ISLAMABAD, Feb. 13 (Xinhua) -- At least seven people were killed and over 40 others injured in a suicide blast outside provincial assembly in Pakistan's Punjab province on Monday evening, local Urdu media and officials said.

Dunya TV said that hundreds of chemists and pharma manufacturers were protesting against a newly introduced act by Punjab government at the busy Mall Road of the provincial capital of Lahore when the blast happened.

Malik Ahmad, Spokesperson of Punjab government confirmed that the blast was carried out by a suicide bomber.

Quoting traffic wardens, local media said that the blast happened when suicide bomber coming on a motorbike blew himself up in the crowd.

The killed included Senior Superintendent Police and a senior officer of traffic police who was negotiating with the protestors to give way to the traffic.

The injured people, including policemen, chemists, and newsmen, have been shifted to nearby state-run hospitals where a state of emergency has been declared.

Hospital sources said that death toll is feared to rise as many among the injured people are in critical condition.

Several vehicles including a Digital Satellite New Gathering (DSNG) van of a local TV channel were completely destroyed in the explosion.

Police and contingent from Pakistan army and paramilitary troops have cordoned off the area for investigation.

No group has claimed responsibility for the attack yet.