Amnesty International has called on the Bahraini authorities to investigate fresh allegations of torture made by some of the 23 detained opposition activists accused of terrorism and plotting to overthrow the government.
According to their lawyers the activists said they had been beaten in prison, deprived of sleep and forced to remain standing for long periods following the first session of their trial on 28 October.
The abuses are said to have been committed to punish the defendants for telling the trial court at its first session that they had been tortured in pre-trial detention following their arrests in August and September.
"The Bahraini authorities must conduct a prompt and independent investigation into both these allegations of torture," said Malcolm Smart, director of Amnesty International's Middle East and North Africa Programme.
"They must also now take steps to protect the 23 defendants from possible further retaliation, following their new allegations."
All 23 men are charged with "forming an illegal organization" aiming to "overthrow the government and dissolve the constitution", inciting people to "overthrow and change the political system of the country", fundraising and planning terrorist acts, and other offences under Bahrain’s 2006 anti-terrorism law. They all deny the charges.
The activists include Dr Abdel-Jalil al-Singace, a leading member of the unauthorized opposition political group al-Haq, and others associated with al-Haq, including religious clerics and civil servants.
Two other opposition activists - Hassain Meshaima', al-Haq's secretary general, and Sa'eed Al-Shehabi, secretary general of the Bahrain Freedom Islamic Movement, who live in London - have been jointly charged with the 23 and are being tried in their absence.
The trial began at the High Criminal Court in Bahrain’s capital, Manama, on 28 October. At the first session all of the defendants entered not guilty pleas, and most told the court that they had been tortured or otherwise ill-treated in pre-trial incommunicado detention.
Some of the accused also said that security officials had threatened them the day before, warning them that they could expose themselves to further torture or abuses if they complained to the court about their torture and other ill-treatment after arrest.
The judge refused to release any of the defendants on bail but agreed to move them all from Dry-Dock Prison in Manama, to protect them against possible abuses by security officials.
However, they all continue to be held at Dry Dock Prison, though in a different section of the prison and no longer in solitary confinement.
The 23 have had very little access to their lawyers. They were only allowed to see them when they were brought before the Public Prosecutor about two weeks after their arrest and again during the first trial session.
At the second session of the court on 11 November, defence lawyers said that some of the defendants alleged that they were subjected to further torture or other ill-treatment after the court's first session.
Lawyers requested fresh questioning of the defendants and the referral of some defendants for independent medical examination, but both requests were rejected.
Only two of the detainees have been referred to doctors outside the prison for an independent medical examination following their allegations of torture.
Two others were referred to the same forensic doctors within the Public Prosecutor's Office who had examined some of the detainees before the trial.
According to lawyers, the medical reports were inconclusive.
A delegation of Amnesty International was present during the first session of the trial. The session was also attended by diplomatic representatives from the embassies of the UK, the USA and France, as well as the media and members of the defendants' families.
Amnesty International observers had the chance to meet lawyers and family members of the detainees in the days before the session.
The third session of the trial will take place on 25 November.
"The authorities must refer all 23 detainees for independent medical examination. They must also grant the detainees regular access to their lawyers and to their families," said Malcolm Smart.