Agence France-Presse quoted lawyer M. Ravi as saying that Singapore authorities did not return his calls or answered his faxed inquiries into his 75-year-old client, who is suffering from medical problems.

Shadrake was arrested at his hotel on 18 July 2010, a day after the launching of his book, "Once a Jolly Hangman: Singapore Justice in the Dock". The 219-page book alleges double standards in the city state's use of the death penalty. It contains a profile of Changi Prison's executioner, Darshan Singh, and also interviews with human rights activists, lawyers and former police officers on cases involving capital punishment in Singapore.

Ravi said he had sent a letter to the police Criminal Investigation Department, asking to see Shadrake, adding that the British author had recurring colon and hernia problems and high blood pressure.

"His condition can worsen if he is under intense pressure....it doesn't help that if he's under constant pressure, it might aggravate his conditions," Ravi wrote in his letter.

AFP reported that the Media Development Authority, which had filed the complaint with the police which led to Shadrake's arrest, claimed that the book is not prohibited in Singapore. The news agency said, however, that no copies of the book can be found in major bookstores and libraries in the city state.