The Marine Assault Team (MAST) (Malay: Unit Gempur Marin, Jawi: اونيت ڬمڤور مارين), formally known as the UNGERIN is a maritime counter terrorism and tactical unit of the Royal Malaysia Police's Marine Operations Force. Having become fully operational in 2007, the UNGERIN conducts anti-piracy and counter-terrorism operations in the coastal waters surrounding Malaysia and assists the marine police to respond swiftly.

UNGERIN operates out of the RMP's Marine Police Main Base in Port Klang, Selangor.

For most operations, the unit is supported by various Malaysian special forces units, including Pasukan Gerakan Khas when crimes takes place in Malaysian waters.

Established in March 2006, the Unit Gempur Marin was created under the Royal Malaysia Police with the first name as the Unit Selam Tempur due to the pressing need of suppressing pirate attacks alongside the coastal area of the Malacca Straits and open sea area of South China Sea which were continuously widespread from time to time despite various efforts done to overcome the problem. Throughout the year of 2006, 239 cases of pirate attacks were reported according to statistics of the International Maritime Bureau, Kuala Lumpur.

As a result of concentrated efforts by Indonesia, Malaysia and Singapore, the piracy activities were drastically reduced. Nevertheless, law enforcement agencies from the three countries continue to be vigilant against pirate activity in the Straits of Malacca.

For the unit's restructuring, the name of UST was changed to Unit Gempur Marin or UNGERIN in the year 2008. Its eventual goal is to have 200 operators on standby with UNGERIN.

The roles of the RMP UNGERIN are predominantly focused on, but not restricted to the littoral and riverine waterborne domains, including:

For this, UNGERIN operators are to patrol the following places: