At least 15 people have died and some 500 have been injured in series of explosions near a military barrack in Equatorial Guinea, officials say.

Sunday’s blasts, in the main city of Bata, were caused by “negligence” around the storage of dynamite at the barracks, the country’s president said.

Images on social media showed huge plumes of smoke and widespread damage. State television showed people looking for survivors in the rubble and lifting up debris from collapsed buildings.

President Teodoro Obiang Nguema said in a statement that the impact of the explosion “caused damage in almost all the houses and buildings in Bata”, and called for international aid.

The incident may have occurred after farmers burned fields surrounding the barracks, he added. In a series of tweets, the health ministry called for volunteer health workers to go to Bata Regional Hospital and also asked for blood donations.