ALCALA DE HENARES, March 13: Spain was burying its dead from the Madrid train bombings on Saturday, as the death toll reached 200 and cast a dark shadow over Sunday's general election.

Campaigning has been suspended since 10 bombs ripped through four packed commuter trains on Thursday. The identity of the perpetrators, which could influence how some people vote on Sunday, remains a mystery.

The government said Basque separatist group ETA remained its prime suspect, but it had not ruled out Muslim militants linked to Al Qaeda. If a Muslim connection is shown, critics of the government could portray the bombings as the result of its unpopular support to Washington over the occupation of Iraq.

Hundreds attended a funeral service in a gymnasium in the commuter town of Alcala de Henares, home to 40 people who died on Thursday and the starting point for three of the four bombed trains.

"We have buried a son, 23 years old, a son full of future," said a father dressed in black, his arm around his wife, at the first public funeral. "We are all overwhelmed."

"It's very hard. We feel uselessness and horror. I can't think about it any more. I don't want to, I don't want to," said a woman named Nieves, who lost a niece called Pilar.

A group tied to Al Qaeda has claimed responsibility for the attacks and ETA has denied it - but neither statement has been confirmed to be genuine.

If the Al Qaeda were to blame, it would be the network's first major strike in the West since the Sept 11, 2001, attacks in the United States.

If it were ETA, it would mean a major escalation in tactics for a group that has killed 850 people over 36 years and is listed as a terrorist group by the United States and European Union.

"Whether it was ETA or Al Qaeda doesn't affect the shared repudiation of terrorism, but it may have different political and electoral consequences," the left-leaning daily El Pais said in an editorial.

Many analysts say any proven ETA involvement in the bombings would probably benefit the ruling party in Sunday's general election because of its tough anti-ETA stance.

But if the attack was proved to be the work of Muslim militants, it could be viewed as the consequence of Mr Aznar's domestically unpopular backing of the invasion.-Reuters