MIRI (THE STAR/ASIA NEWS NETWORK) - A tourist from Germany and a local tour guide have reportedly gone missing in Malaysia's Mulu caves in northern Sarawak due to a sudden flash flood on Friday evening (July 12).

Eight other tourists are said to be safe, after having escaped the flood in the cave.

The Sarawak fire and rescue department said the police in Mulu have sought its help to carry out urgent rescue efforts.

The department, also known as Bomba Sarawak, had mobilised its special search and rescue unit, after being notified of the missing persons by the police at about 6pm on Friday.

"The flash floods happened in Gua Rusa (Deer Cave). The police notified us about 6pm," said Bomba Sarawak in an update.

The identities and nationalities of all the tourists have not been ascertained as yet.

Rescue teams from Marudi and Miri were preparing their search teams, and a helicopter unit from Miri was also being readied.

Mulu is about 200km inland from Miri city.