Spanish firefighters found a dead man on Sunday as they combed through the wreckage of a Madrid bar destroyed by an explosion that left 25 people injured, two seriously.

A gas leak is suspected of having triggered Saturday's blast in the capital's Vallecas neighborhood, but city officials have said it is too early to establish a cause.

Firefighters aided by sniffer dogs painstakingly cleared the rubble by hand on the ground floor amid the collapsed walls and framework.

"The work has been pretty complicated, with lots of personnel, because it has been necessary to go more or less stone by stone and brick by brick," said fire service spokesman Javier Ramos.

Madrid emergency services confirmed on X that a man's body was found early on Sunday morning, with a civil protection psychologist supporting the relatives.

They also said 25 people had been treated, with two in a "serious" condition taken to hospital.