Yemeni security officials say a suicide bomber has blown himself up at a checkpoint in the country's south, killing four soldiers and wounding six.

The officials say the bomber approached the checkpoint in the area of al-Mansoura in the southern city of Aden on Wednesday and detonated his explosives among the soldiers, some of whom were having lunch.

The officials spoke on condition of anonymity because they are not authorized to speak to the media.

Aden, which has been the seat of Yemen's internationally recognized government since April last year, has been hit by a series of suicide bombings and other deadly attacks that were carried out either by al-Qaida's Yemen branch or the country's Islamic State affiliate.

In 2014, Yemen's Shiite rebels known as Houthis captured the capital, Sanaa.