The trial began amid tight security two days before a second round of legislative elections in Bahrain, after opposition members won 18 of Parliament's 40 seats in the first round on Oct. 23.

Twenty-five of the 27 defendants appeared before the High Criminal Court in Manama charged with "forming an illegal organization, resorting to terrorism, financing terrorist activities and spreading false information," according to their indictment.

The defendants who appeared in the court rejected the charges, while the other two accused are being tried in absentia as they are abroad.

"We're not guilty," they said in turn while complaining of having been "tortured" and "abused" and denouncing their continued detention in solitary confinement.

Some of the charges carry a sentence of life imprisonment, defense lawyers said.

"We were subjected to physical and mental torture (and) were placed in solitary confinement," said Abduljalil Al-Singace, one of the defendants who needs a cane and a wheelchair to move.

"My health is deteriorating and I did not have access to necessary medication," Al-Singace, an official from the opposition group Haq, told the court.

Another of the accused, preacher Sheikh Mohammed Al-Moqdad, said he had been "beaten, subjected to electric shocks, sleep deprivation and humiliation."

The court declined to investigate their allegations of torture, a defense lawyer said, but did agree for three of the accused to be examined by doctors.

The court also agreed to transfer the detainees from a state security prison to a regular detention facility and to allow them to be visited by their families and lawyers.

The judge Ibrahim Al-Zayed set the next trial session for Nov. 11.

Riot police were stationed around the courthouse for the trial. Only one family member for each suspect was allowed in the court gallery alongside observers that included US and European envoys, Amnesty International and other rights groups. The proceedings were covered by Bahrain's state television, but reporting restrictions were placed on other local journalists.

Authorities announced Sept. 4 that they had charged 23 activists, two of them in absentia, with forming a "terror network" aimed at toppling Bahrain's government.

Four new defendants appeared in court on Thursday.

On Oct. 21, Bahrain said Interpol had circulated warrants for the arrest of two opposition leaders who have been living in London, Bahrain Freedom Islamic Movement Secretary-General Said Al-Shihabi and Haq leader Hussein Mashaimaa.

The original group of 23 includes prominent rights activist Al-Singace, who was taken into custody Aug. 13 as he returned from London with his family. The other alleged coup plotters range from professors, taxi drivers and a dentist — all facing possible life sentences if convicted.