A powerful blast outside a famous Sufi shrine in Pakistan's second largest Lahore city on Wednesday killed at least five persons, including two policemen, and injured many others as the country marks the fasting month of Ramzan, police said.
The blast targeted a van carrying police officers outside the Data Darbar shrine, the largest Sufi shrine in South Asia.
According to initial police reports, the explosion took place close to two police vehicles near Gate 2 of Data Darbar in Punjab province.
Three police officials died in the blast, a security guard and a resident were also among the dead, Deputy Inspector General Operations Lahore Ashfaq Ahmad Khan was quoted as saying by the Geo News.
At least 24 people are being treated for injuries, some of whom are in critical condition, he added.
The exact nature of the blast was being ascertained, and it was too early to determine if it was a suicide attack, the official told media from the site of the incident.
Police have cordoned off the area and ascertaining the nature of the blast.
A police official said their teams are working on evaluating the incident.
"All departments, including the Counter Terrorism Department are working. We will not spare any efforts for the security of the citizens," he added.
Prime Minister Imran Khan has strongly denounced the blast outside Data Darbar in Lahore and sought a report from the authorities, Radio Pakistan reported.
The premier has commiserated with the bereaved families and directed authorities concerned to provide best possible medical treatment to those injured in the blast.
Entry to the Data Darbar was sealed in the aftermath of the blast.
The shrine is visited by hundreds of thousands of people each year.
In 2010, the shrine was targeted in a suicide attack that killed more than 40 people, and is guarded by heavy security.