An Islamic terrorist group linked to Al Qaeda has claimed responsibility for the Madrid attacks.

An email to the London-based Al-Quds Al-Arabi newspaper said� the Brigade of Abu Hafs al-Masri was responsible for the worst terrorist attack on a European city since the second world war.

Bari Atwan, the newspaper’s editor, told Sky News he was certain the email was authentic.

The claim comes after investigators found an Arabic language tape with Koranic versus in a van carrying bomb detonators near Madrid.

The letter and the discovery of the van may throw into doubt the Spanish government’s claim that the Basque separatist group Eta - rather than al Qaeda - was behind the multiple bombings, which also injured1,200 people.

“Because of this, I have just given instructions to the security forces not to rule out any line of investigation,” Angel Acebes said.

I think we may have just seen the opening salvo in the Islamic war against Europe.