Once A Jolly Hangman, Police said the 75-year-old Alan Shadrake is being investigated for alleged criminal defamation and other offences.
British author Alan Shadrake was arrested by Singapore police at a hotel at 8am on Sunday.
The arrest was made after a police report by the Media Development Authority on Friday.
Shadrake has also been served with a Contempt of Court order by the Attorney-General.
It is believed the arrest is linked to his latest book, “Once a Jolly Hangman – Singapore Justice in the Dock” launched on Saturday night.