Sufi shrine hit in Pakistan bomb attack

At least four people have been killed in a bomb blast outside a Sufi shrine in eastern Pakistan, police said, the latest in a wave of militant attacks in the nuclear-armed nation.

Two men riding a motorbike left a milk container near the gate of the shrine in Pakpattan, 190 kilometres from the Punjab provincial capital Lahore, which then exploded in a huge fireball, a witness said.

"We have four killed and about 12 wounded," regional police chief Mohammad Kashif told reporters. "The rescue work is over. We're now investigating."

Sufi worshippers have frequently been the target of bloody attacks by Islamist militants in Pakistan.

The blast blew up a boundary wall and damaged several shops and stalls outside the shrine where the 12th century saint, Baba Farid, also known as Ganjshakar is buried, witnesses said.

Police said the mausoleum of Baba Farid was undamaged, adding that the blast took place near the eastern gate which was already closed for security reasons.

The Pakpattan site is the second most popular after the Data Darbar shrine in the eastern city of Lahore, where two suicide bombers blew themselves up among crowds of worshippers in July, killing 42 people.

On October 7, two suicide bombers blew themselves up at a Sufi shrine of Abdullah Shah Ghazi in Karachi, Pakistan's biggest city, killing nine worshippers, including two children.