KAMPAR: Some 30 people were trapped in Gua Tempurung here when heavy rains made the main entrance impassable.
It was learnt that they were filming a Hong Kong-produced movie in the cave during the 4pm incident. The condition of those trapped is yet to be known.
District police chief Superintendent Mohamad Nazri Daud said the heavy downpour started at 3pm today.
"The rescue operation is being carried out and we will bring them out using the back exit," he said, adding that it was still raining in the area.
Gua Tempurung is known as one of the longest and largest limestone caves in Peninsular Malaysia.