Security forces are on alert in Spain as a court began delivering its verdict on the March 2004 Madrid train bombs, the country's largest terror trial.
The judges are ruling on a total of 28 defendants
A three-judge panel began its summary at 1130 (1030 GMT) on Wednesday, to be followed by verdicts and sentences.
Twenty-eight people faced trial over the devastating nail-bomb blasts that hit four commuter trains, killing 191 people and injuring more than 1,800.
All the accused pleaded innocent during the four-month trial.
Judge Javier Gomez Bermudez has been reading the summary.
He has said that there is no evidence of involvement by the Spanish separatist group Eta.
The judge also said that all, if not almost all, the explosives used came from one source - a Spanish mine.
The judge said that one backpack that did not detonate and supplied vital evidence was definitely linked to the attacks.
The BBC's Dominic Hughes in Madrid says much of the judge's summary has been dismantling defence arguments.
There are 28 defendants, 27 men and one woman, 19 mostly Moroccan Arabs and nine Spaniards, who faced charges including murder, forgery and conspiracy to commit a terrorist attack over the 11 March 2004 blasts.
MADRID TRAIN BOMBINGS
Bombs killed 191 people, injured 1,841
Ten backpacks filled with dynamite and nails blew up on four packed commuter trains
Twenty-eight on trial - 19 Arabs, mostly Moroccans, and nine Spaniards
Seven top suspects blew themselves up during police raid in April 2004
Prosecutors believe bombings were an Islamist plot
All defendants pleaded innocent
The top eight defendants each face nearly 39,000 years in jail if found guilty on all charges, but under Spanish law the maximum sentence for terrorism is 40 years.
Spanish investigators say the accused were part of a local Islamist militant group inspired by al-Qaeda, but had no direct links to the terror organisation.
Fourteen of the accused went on hunger strike during the trial, in protest against what they called unjust accusations against them.
Seven suspected ringleaders died in a suicide blast in a Madrid apartment three weeks after the attacks.
Spanish Prime Minister Jose Luis Rodriguez Zapatero says he hopes the ruling will "give a definitive answer to those who have put forth absurd and despicable doubts about 11 March".
Many Spaniards still have serious doubts about who was behind the attacks, says the BBC's Danny Wood in Madrid.
Some theories - supported by a number of victims - suggest they were part of a coup d'etat involving Spain's secret services.
But many others believe the verdict will clear up such doubts, and regard it as a key step towards recovery, our correspondent says.
Memorial services are planned for a week after the verdict.