Two people have been killed and several wounded in a series of explosions at an arms storage depot in the southern Yemeni port city of Aden, reports say.
The blasts in the Jabal Hadid area were caused when old munitions exploded due to heat and friction, according to Aden's governor, Ahmad al-Kahlani.
Eyewitness described plumes of smoke rising from the area and army vehicles and ambulances heading to the scene.
Rush-hour traffic built up as the area was sealed off by security forces.
Residents told the Associated Press news agency that the blasts continued for about 45 minutes.
They said two houses had caught fire and several buildings nearby had their windows blown out.
Aden's governor said the facility was being evacuated when the blast occurred.
A medical source told Reuters news agency that two women were killed and a man was wounded when their bus was hit by shrapnel. Several others in the vicinity were injured in the blasts.
Aden was the site of a bomb attack on a US warship in October 2000, which killed 17 sailors - an attack blamed on Osama Bin Laden's al-Qaeda network.
A French oil tanker was also bombed in Aden in 2002, killing one crew member.