At least six people have died and one was injured in the explosion on Saturday of an asphalt tank in an industrial zone in Gabès, in south-eastern Tunisia.

The explosion, "the causes of which are not yet known", occurred at 9:30 am local (08:30 GMT).

"We made in a first preliminary assessment six dead and one wounded", Moez Triaa, the spokesperson for civil protection said.

Four people died on the spot and the other two after being transported to a hospital in Gabès.

Search operations to find other possible victims are still ongoing, added Mr. Triaa, without being able to give more details.

According to photos published by local media, a huge black smoke covered part of the industrial zone of Gabès.