RIYADH (Reuters) - Around 25 former detainees from Guantanamo Bay camp returned to militancy after going through a rehabilitation program for al Qaeda members in Saudi Arabia, a Saudi security official said on Saturday.

The United States have sent back around 120 Saudis from the detention camp at the U.S. naval base in Cuba, set up after the U.S. launched a “war on terror” following the September 11 attacks by mostly Saudi suicide hijackers sent by al Qaeda.

Saudi Arabia, the world’s top oil exporter, has put the returned prisoners along with other al Qaeda suspects through a rehabilitation program which includes religious re-education by clerics and financial help to start a new life.

The scheme, which some 300 extremists have attended, is part of anti-terrorism efforts after al Qaeda staged attacks inside the kingdom from 2003-06. These were halted after scores of suspects were arrested with the help of foreign experts.

Around 11 Saudis from Guantanamo have gone to Yemen, an operating base for al Qaeda, while others have been jailed again or killed after attending the program, said Abdulrahman al-Hadlaq, Director General of the General Administration for Intellectual Security overseeing the rehabilitation.

He pinpointed strong personal ties among former prisoners but also tough U.S. tactics as the reason why some 20 percent of the returned Saudis relapsed into militancy compared to 9.5 percent of other participants in the rehabilitation program.

“Those guys from other groups didn’t suffer torture before, the non-Guantanamos (participants). Torturing is the most dangerous thing in radicalization. You have more extremist people if you have more torture,” Hadlaq told reporters in a rare briefing about Saudi anti-terrorism efforts.

REHABILITATION SCHEME “A SUCCESS”

Despite the setback with Guantanamo prisoners, Saudi Arabia regards the rehabilitation scheme, which kicks in after militants have served a prison term, as a success.

“There is no doubt that there is an effect,” Hadlaq said.

U.S. President Barack Obama ordered the camp shut after taking office in January 2009 but his plans have been stymied. There are now about 180 detainees left, among them 13 Saudis. At its peak, the camp held about 780 detainees.

More than 2,000 sympathizers of al Qaeda are still in prison in Saudi Arabia. Some 2,000 teachers have been removed from classrooms for their extremist views in the past five years while 400 teachers are in prison, Hadlaq said.

Saudi Arabia plans to build five more rehabilitation centers which will be able to accommodate 250 people each, he said.

The expansion plans are partly to cope with the eventual release of 991 suspected al Qaeda militants whom the authorities said in October were awaiting trial for 30 attacks since 2003.

In July, a Saudi court sentenced one unnamed Islamist to death and handed out to others jail terms of up to 30 years in the first publicly reported trials since the arrests.