A bomb went off on Monday at a busy district in a southern Yemeni city, killing 13 people and wounding an unspecified number, according to security officials.

They said the explosion struck a market in Qataba, in the southern Dhale province, but provided no further details.

No one immediately claimed responsibility for the attack, but al-Qaida and Islamic State militants are active in southern Yemen.

The officials spoke on condition of anonymity because they weren't authorized to speak to the press.

Dhale is controlled by forces loyal to the internationally recognized government, which is at war with Shiite rebels known as the Houthis and their allies. A Saudi-led coalition has been fighting alongside the government since 2015. AP