Three crew members died when a semi-submersible barge owned by PACC Offshore Services Holdings (POSH) sank off Indonesia on Friday.

The Singapore-flagged, 2012-built, POSH Mogami sank 2 nm off Sekupang, Batam Island Indonesia, with nine crew onboard, according to the Maritime & Port Authority of Singapore (MPA).

“It was reported that the semi-submersible barge was carrying out submerging trials at the time of the incident,” the MPA said.

It said the Indonesian authorities had rescued six crew members and recovered the bodies of three who died in the accident. The three who died were Singapore, Myanmar and Chinese nationals teh MPA said.

According POSH’s website the 30,500 dwt semi-submersible barge was classed by ABS.

As the flag state MPA said it was investigating the cause of the accident.

POSH is listed on the Singapore Exchange and part of the Kuok Group.