Bahrain's public prosecutor has decided not to release Nabeel Rajab, a prominent activist, after a court ordered his release hours earlier.

The public prosecutor said in a statement on Wednesday that Rajab would not be released pending other charges related to a case where he had been questioned about spreading false rumours about the country's internal situation.

The statement did not specify the charges, but it is believed that opinion pieces he wrote for The New York Times and France's Le Monde newspapers while in custody or earlier statements he made to an outside TV network, are being used as justification for the new charges against him.

Jalila Sayed, the defence lawyer, confirmed that Rajab, 51, who has been in jail since June, would continue to be held after earlier saying he suffered from poor health.

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"Nabeel is overall weak because of so many health problems he started facing, including heart problems and other physical issues," Sayed told Associated Press news agency.

"He's under tremendous stress because of this length of detention."

Rajab was arrested over a series of messages posted to his Twitter account about the ongoing conflict in Yemen, as well as allegations of torture by authorities at a local prison.

In Wednesday's hearing, Sayed said she believed the court initially granted bail because a witness for the prosecution could not specifically prove that Rajab had control of the Twitter account in his name, nor show he sent the tweets in question.

"We hope this will end with an acquittal because the case has no evidence," the lawyer said.

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Source: News agencies