The joy of bathing for two siblings from a homeless family at the Tanjung Lobang Beach, Monday turned tragic when they both drowned.

Miri Fire and Rescue chief Law Poh King said, Nuraini Abdullah, six, and her brother, Suhaid Abdullah, five, were bathing near a concrete jetty, in front of the stall where they lived in, without their 28-year-old mother's supervision.

"The mother only noticed her children's disappearance after her youngest son, three, came back to the stall alone," he said.

Law said the woman tried to locate the siblings but failed.

A search and rescue team was rushed to the scene after receiving an emergency call at 4.56pm.

"The siblings' bodies were found at the beach at 5.07pm by a security guard," he said.