A London-based Arabic newspaper says an al-Qaeda-linked group has claimed responsibility for the series of deadly bombs that ripped across a train line in Madrid, but Spanish officials maintain Basque separatists are still the chief suspects.

The newspaper Al-Quds al-Arabi said it received a five-page e-mail from the Brigade of Abu Hafs al-Masri claiming its "death squad" had penetrated "one of the pillars of the crusade alliance, Spain."

About 190 people died Thursday when 10 bombs exploded on the trains.

Police officers by the wrecked train at the Atocha railway station in Madrid, Spain. (AP photo)

"This is part of settling old accounts with Spain, the crusader, and America's ally in its war against Islam," the unverified claim said.

The statement also warned that an attack would soon be launched against the United States.

"We announce the good news for the Muslims in the world that the strike of the black wind of death, the expected strike against America, is now at its final stage – 90 per cent ready – and it is coming soon, by God's will," the claim said.

One of the destroyed cars (AP photo)

The group said it did not feel sad for the "so-called civilians," apparently referring to the casualties in Madrid.

"Is it OK for you to kill our children, women, old people and youth in Afghanistan, Iraq, Palestine and Kashmir? And is it forbidden to us to kill yours?" the claim asked.

The claim comes as police investigating the bombings say they found a van with detonators and an Arabic-language tape with Qur'anic verses in a nearby town.

Spain's Interior Minister Angel Acebes said the van, found in Alcala de Henares, contained seven detonators and the tape.

Photo Gallery: Scene of the wreck

More than 1,200 were injured in the bombings during the Thursday morning rush hour.

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

Government officials had initially blamed the Basque separatist group ETA for the attack, which came just days before elections scheduled for Sunday.

"This is mass murder," said Prime Minister Jose Maria Aznar. "No negotiation is possible or desirable with these assassins who so many times have sown death all around Spain."

The bombs began going off at about 7:50 a.m. along a 15 kilometre stretch of rail line between Santa Eugenia and Atocha.

Ten of them went off within 10 minutes. Police found three other bombs which hadn't exploded.

A Basque politician denied that separatists had set off the bombs. Arnold Otegi suggested that "Arab resistance" could have planned the attack in revenge for Spain's support for the invasion of Iraq.

Otegi also noted that ETA had not issued a warning prior to the attacks, a hallmark of other ETA bombings.

World leaders reacted with outrage at the carnage in Madrid.

"The United States stands resolutely with Spain in the fight against terrorism in all its forms," said American Secretary of State Colin Powell.

British Foreign Secretary Jack Straw called the bombings a "disgusting assault on the very principle of European democracy."