ISLAMABAD (AFP)- A blast tore through a truck carrying paramilitary soldiers in restive northwest Pakistan on Thursday, killing 30 people and wounding at least a dozen more, a senior security official said.

The vehicle, which was packed with ammunition, was travelling outside Mingora, the main city in the scenic Swat valley in North West Frontier Province, when the explosion occurred, the official said.

“Thirty people were killed in the explosion including 17 paramilitary soldiers. The damage was high because the truck was packed with ammunition,” the official, who asked not to be named, told AFP.

A doctor at a local hospital said 10 bodies had been brought in so far.

“Ten dead bodies were brought to Saidu Sharif hospital, and 35 wounded people. Some of the bodies are charred,” doctor Nisar Khan told AFP.

Security sources said a suicide bomber detonated his explosives near the truck, but the government said the truck’s cargo could have triggered the explosion.

“The nature of the blast is not clear and it is being ascertained. There was ammunition in the truck which caused the damage,” interior ministry spokesman Javed Cheema told AFP.

The explosion comes just one day after Pakistan deployed more than 2,000 troops to the scenic Swat valley to bolster efforts to stem rising violence linked to pro-Taliban militants.

The district was once one of Pakistan’s premier tourist attractions, but the area in conservative North West Frontier Province, bordering Afghanistan, has become a stronghold of banned group Tahreek Nifaz-e-Shariat Mohammadi (TNSM).

The radical group has close ties to Taliban fighters who have been mounting attacks on government officials and security forces in the area.

No one immediately claimed responsibility for Thursday’s attack.

Hundreds of Taliban militants fled over the Afghan border into Pakistan’s nearby tribal areas after the fall of the Taliban in a US-led invasion in 2001.

Pakistan’s military has suffered a string of deadly attacks since government troops stormed the Al-Qaeda-linked Red Mosque in Islamabad in July.

Most of those attacks have been suicide blasts that have killed about 400 people since July, according to an AFP tally.

The military said Wednesday that the deployment of troops into Swat was aimed at improving law and order in the troubled region.