PIRATES struck four times near Batu Berhenti beacon in the Straits of Singapore in the last three months, robbing crew members of their personal belongings and cash.

The most recent piracy happened at 1.30am on Monday.

Five robbers, armed with parangs, boarded the Indonesia-registered tugboat , the Maju Daya 3, that was towing the Marcopolo 188, a Singapore-registered barge.

They made off with money and personal papers. Fortunately, no one was hurt.

The boats continued to Batu Ampar in Indonesia after the incident and the ship master reported the matter to Singapore's Port Operations Control Centre.

According to the ReCAAP Information Sharing Centre, this is the fourth piracy in the vicinity of Batu Berhenti beacon in the last three months.

The first happened on Sept 8, involving a Singapore-registered tugboat enroute to the island from Vietnam.

The next two cases, which occurred on Oct 4 and Oct 31, involved a Malaysian registered coaster and a tanker respectively.

None of the crew in these cases was injured.

In its statement to the media on Tuesday, ReCAAP said although there is no conclusive evidence, it appeared that they were the works of the same group.

'In all four incidents, the robbers came alongside the ships in their boat during hours of darkness, boarded the ship while underway and escaped with the crew's belonging', it said.

ReCAAP is the Regional Cooperation Agreement on Combating Piracy and Armed Robbery against Ships in Asia (ReCAAP), the first government-to-government pact to enhance the security of regional waters.