A desperate search for survivors is underway after a two-storey restaurant collapsed on the Spanish island of Majorca on Thursday night, killing at least four people and injuring 16.

Several people are believed to be trapped under rubble at the site of the Medusa Beach Club, a beachside restaurant in one of the busiest areas of the regional capital, Palma de Majorca.

Police said the victims are a Spanish man, two German women and a Senegalese man.

The collapse of the building caused people to fall into the basement below, where there were customers and staff.

Police say the terrace caved in because of excessive weight.