A bomb blast on Monday wounded at least 39 people in the eastern Pakistani city of Lahore, a government official said, with no one immediately claiming responsibility.

Attacks in the Punjab provincial capital have become less frequent over the past couple of years but Islamist militant groups are still active there and periodically carry out major attacks.

"It was a bomb blast in a fruit truck that wounded more than 30 people," provincial Punjabi government spokesman Malik Muhammad Ahmad Khan said.

Haider Ashraf, deputy inspector general of police, said the truck was loaded with explosives and experts were combing through the wreckage.

"Allah has saved Lahore from big destruction," Ashraf told local media.

Last month a suicide bomber from the militant group Pakistani Taliban killed at least 25 people in Lahore, many of them police.