The interior ministry accused Nabeel Rajab, head of the Bahrain Centre for Human Rights, of tampering with photos of a man who died in custody last week. A statement posted on the ministry’s official website late Sunday said Mr. Rajab posted on his Twitter account a "fabricated image" of a detainee, Ali Isa Saqer.

Bahrain’s leading human rights activist will be questioned by a military prosecutor, according to the Gulf country’s interior ministry that has been leading the crackdown on Shiite protests against Sunni rulers.

The interior ministry accused Nabeel Rajab, head of the Bahrain Centre for Human Rights, of tampering with photos of a man who died in custody last week. A statement posted on the ministry’s official website late Sunday said Mr. Rajab posted on his Twitter account a “fabricated image” of a detainee, Ali Isa Saqer.

Mr. Rajab claims Saqer was fatally beaten in custody. He told The Associated Press that the photo he had posted on his Twitter account was genuine, showing Saqer’s body covered with bruises and gashes. Mr. Rajab said the campaign against him is aimed at preventing him from documenting human rights abuses in Bahrain.

Mr. Rajab said he has not been contacted by the interior ministry and only learned of the planned questioning from the ministry’s website.

“They want to do their crimes in secret,” Mr. Rajab said of Bahrain’s government. “I am one of the few human rights activists who has not yet been arrested and the government wants to silence me and prevent me from doing my work.”

Authorities have sharply tightened Internet and media controls under the military rule imposed last month to quell protests by Shiite majority against the Sunni monarchy that has ruled Bahrain for more than 200 years.

Bahrain declared martial rule on March 15. Hundreds of Shiite activists, anti—government protesters and opposition leaders, demanding greater political freedoms and equal rights have been detained.

At least 29 people have been killed since Feb. 14 when protests began in the strategically important Gulf kingdom, the home of the U.S. Navy’s 5th Fleet. Among the dead are also two opposition supporters who died in custody.

Authorities claim Sager died on Saturday after struggling with guards. A government photo shows few signs of injuries.

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