Johor police have detained four more individuals to assist investigations into the death of Estonian model Regina Soosalu on Pulau Rawa, Mersing on July 1.

Johor CID chief Datuk Hasnan Hassan said those detained were three men and a woman aged from 24 to 27 years.

All of them were picked up in Mersing on Tuesday, he said in a statement here.

He also said from Sunday till Tuesday, police had released three individuals who were held in connection with the case after their statements were recorded.

However, two other men were still being held by police in connection with the case, he added.

Hasnan also asked the public not to speculate on her death and urged anyone with information on the case to call the Johor Police's operations room at 07-2212999.

The 30-year-old woman, who had been living in Kuala Lumpur, had arrived on the island on July 1 and was found dead in the sea on the same day.

Initially, police had investigated the case as a drowning incident but classified it as a murder case after finding injuries on the body.