Abdul Kareem al-Fakhrawi, a prominent Bahraini businessman, was martyred on Tuesday due to severe torture while in prison

Abdul Kareem al-Fakhrawi, a prominent Bahraini businessman, was martyred on Tuesday due to severe torture while in prison, the opposition al-Wefaq group said.

Fakhrawi is the fourth Bahraini, tortured to death, since anti-government protests began in the country in mid-February. The 49-year-old businessman disappeared on or around April 4, when he went to file a police report against policemen who had earlier raided his home, reports said.

Fakhrawi had been a potential parliamentary candidate in Bahrain's 2006 elections.

The circumstances surrounding his disappearance, detention, and death remain unclear but according to sources his brother identified the body at a local morgue. The Bahrain interior ministry has not commented on the incident.

Fakhrawi owned the Fakhrawi bookshop chain and was an investor in the independent daily al-Wasat.

His death comes just a day after Bahrain buried blogger Zakria Rashid al-Asherri, 40, martyred while in police custody.

Bahraini forces have severely suppressed the anti-regime protests with the help of Saudi, the UAE and Kuwaiti troops.

Signs of abuse on bodies of detained

In recent days Human Rights Watch, Amnesty International, and Doctors Without Borders/Medecins Sans Frontieres (MSF) among other rights groups had criticized the Bahraini government crackdown.

“Bahrain should investigate the death in police custody of three people,” U.S.-based HRW said on Wednesday, saying one of the bodies bore signs of physical abuse.

The opposition says hundreds have been arrested and four have died in police custody over the past 10 days.

"It's outrageous and cruel that people are taken off to detention and the families hear nothing until the body shows up with signs of abuse," said Joe Stork, deputy Middle East director for the New York-based group.

HRW said it had seen the body of Ali Saqer, one of the men who died in police custody, and that it bore signs of severe physical abuse.

Bahrain has accused human rights activist Nabeel Rajab, head of the Bahrain Center for Human Rights, of doctoring pictures of the corpse. "We viewed Ali Saqer's body just prior to his burial and its condition was exactly as shown in the photo that Nabeel Rajab circulated," Stork said.