The Crime Library is appealing for information about the whereabouts of Mr Chew Khoon, an 81-year-old Singaporean, who was last seen by his family on May 3.

He is believed to have driven his black E200 Mercedes Benz into Johor Baru, Malaysia on that day, according to the voluntary group which helps to track missing people here.

The retired businessman was last seen wearing a white collared shirt, grey pants and black leather shoes. His son, Mr Chew Gim Hock, said his father commutes regularly across the Causeway because of their family owns two plots of land in Johor. The older Mr Chew also owns a home there.

"The last time I saw him was the evening of May 2. [My father] and I talked and reminisced. He spoke to me about kampong stuff," said the son. Mr Chew, 53, said the family has since filed police reports both in Singapore and Malaysia but is appealing to anyone with information pertaining to the whereabouts of his father to call the Crime Library 6293 5250.