Fenech, a key player in Malta's energy sector, has been described as a "person of interest" in the murder of Maltese investigative journalist Daphne Caruana Galizia. She was killed by a car bomb in Malta on Oct. 16, 2017, according to local media reports.
Fenech's first arrest came less than 24 hours after Prime Minister Joseph Muscat had offered a conditional pardon to a man who claims to know the mastermind behind Caruana Galizia's murder if such information could be corroborated in court.
However, on Friday, Muscat said the middleman, identified by MaltaToday as taxi driver Melvin Theuma, had not yet given sufficient information to justify this pardon.
Fenech had subsequently been released on police bail late Thursday night, as under Maltese law suspects can only spend 48 hours in police custody before they must be charged or released on bail. He was re-arrested hours later.
Police have yet to make an official statement.