Another bomb was found following Thursday’s bombings of four Madrid trains that killed 192 people, radio reports said on Friday.
The undetonated bomb was found under a pile of luggage which had been deposited after the terrorist attacks in a police station in the southeast of Madrid.
The bomb, hidden in a bag, was defused.
Officials discovered it when a cellohone rang, which was likely meant to remotely trigger the explosive device. The mechanism failed.
Meanwhile, medical officials said on Friday that forensic experts had so far been unable to identify some 60 of the dead.
The maimed bodies of the victims have been transferred to a makeshift morgue set up in a requisitioned exhibition centre in the Spanish capital.
Medics had expected to publish a full list of the dead in the early hours of Friday.
The interior ministry meanwhile published on its website a list of the names of 1 175 of the more than 1 400 people who survived the carnage with injuries.
Madrid’s hotel association and two hotel chains offered to accommodate families of the victims for free. – Sapa-DPA