Police cordon off a nearby street following a terrorist attack in central Barcelona, Spain. Picture: Xinhua/Ying Qiang

Madrid - The Catalonia police on Sunday said investigators were still working on the hypothesis of 12 suspects in the Barcelona attacks that took place on Thursday and that one man was still sought.

Speaking to local radio, spokesman Albert Oliva said this man was Moroccan-born 22-year-old Younes Abouyaaqoub.

He also said he could not confirm whether more than one person had died in a house blast in the town of Alcanar on Wednesday.

"It could be one, two or three," Oliva said.