A suspected Al Qaeda cell leader was convicted Monday of conspiring to commit murder in connection with the Sept. 11 attacks (search) in the United States, concluding Europe's biggest trial of alleged members of the terrorist group.

Imad Yarkas (search), one of 24 defendants on trial, was sentenced to 27 years in prison for conspiracy and of being a leader of a terrorist organization.

Prosecutors had accused Yarkas, a 42-year-old Spaniard of Syrian origin, of the more serious charge of being an accomplice to murder and requested a jail term of nearly 75,000 years — 25 years for each of the nearly 3,000 people killed in the suicide airliner attacks in 2001.

Two other suspects were acquitted of charges of helping plot the Sept. 11, 2001, attacks, although one of them was found guilty of collaborating with a terrorist organization.

Twenty-one others also stood trial, but on charges not directly related to Sept. 11. Of those, 16 were convicted of belonging to or collaborating with a terrorist organization and five were acquitted.

One of the 16 was Tayssir Alouny, a correspondent for the pan-Arab TV network Al-Jazeera (search). He was convicted of collaboration and sentenced to seven years in jail.

Al-Jazeera condemned Alouny's verdict.

"It was a black day in the history of the Spanish justice," Al-Jazeera news editor Ahmed al-Sheik told the broadcaster from Madrid. "We were all shocked because everyone expected Alouny to be freed. It is a regrettable event in the history of international journalism when a journalist who sought the truth becomes the accused."

All 24 were expressionless as the verdicts were read in the National Court.

Yarkas had been charged with arranging a meeting in the Tarragona region of Spain in July 2001 at which key Sept. 11 plotters — alleged suicide pilot Mohamed Atta (search) and plot coordinator Ramzi Binsalshibh (search) — met to decide last-minute details, including the date of the massacre.

Another suspect, Moroccan Driss Chebli (search), was also alleged to have helped set up the meeting. He was acquitted of murder charges but convicted of collaborating with a terrorist group and sentenced to six years.

The third suspect facing specific Sept. 11 charges, Ghasoub al-Abrash Ghalyoun (search), was acquitted. The Syrian-born Spaniard was indicted over detailed video he shot of the World Trade Center (search) and other landmarks during a trip to several U.S. cities in 1997.

"The lack of evidence to show the three suspects took part in such despicable murders, either as material participants ... or as accomplices or harborers, is absolute," the 450-page sentencing report said.

"The only thing proven is Yarkas' conspiracy with the suicide terrorist" Atta and other members of the Hamburg, Germany-based cell that staged Sept. 11, it said.

Judge Baltasar Garzon had said the tapes were passed on to Al Qaeda and amounted to the genesis of planning for the attacks on the U.S. Ghalyoun said during the trial he shot the tapes as an innocent tourist.

Ghalyoun was also acquitted of charges of being a member of a terrorist organization.