Twelve died in an explosion near Aden airport

Shafaq News/ A car exploded near the entrance to the international airport of Yemen's southern port city of Aden on Saturday, resulting in 12 casualties, witnesses and security sources told Reuters, but it was not clear whether the incident was an attack.

One security source said the car exploded at an outer entrance to the airport near an airport hotel.

Aden is the temporary home of Yemen's internationally-recognised government, which has as part of a coalition backed by Saudi Arabia been fighting the Iran-aligned Houthi group for around seven years.

But tensions have also for years simmered within Aden itself between the government and southern separatist groups.

The government and the Southern Transitional Council (STC) are nominal allies under the Saudi-led coalition.

Earlier this month a car bomb in Aden targeting a convoy carrying the city's governor - an STC member - killed at least six people and wounded others. The governor survived.

Instability in the south complicates United Nations-led peace efforts to end the war in Yemen which has killed tens of thousands of people and left 80% of the population needing help.