The device exploded in a hamburger restaurant in the resort of Torrevieja.

Police had cordoned off the area and no-one was hurt.

They said the device contained about four kilogrammes of explosives.

Earlier this week, a bomb exploded in the nearby town of Santa Pola, killing two people, including a six-year-old girl.

ETA announced earlier this year that it would launch attacks specifically targeting tourist resorts this summer, as part of its campaign to stop foreign tourists visiting Spain.

Anonymous call

Basque nationalist newspaper Gara said it had received a call in the name of ETA saying two bombs would explode at 1200 GMT, one in Torrevieja and the other in Santa Pola.

Santa Pola beach was evacuated of holidaymakers, but no device was found.

ETA has killed some 800 people since 1968 in a bloody campaign for an independent Basque homeland in northern Spain and south-western France.

Following Sunday's bombing, the Spanish Government began moves to activate a ban on ETA, made possible by new legislation.