Early one October morning in 1969, Singapore police officers found the body of a man dumped in a storm drain. He had been stabbed to death, police said, in what became one of the country's most notorious gang killings.

After more than 50 years on the run, one of the men wanted for the murder, Tan Tong Meng, died of a heart attack in Denmark last month, according to former police detectives, online tributes and media reports.

The death of one of Singapore's most high-profile gangsters, and memories of the brazen 1969 mob hit, have revived interest in the city-state's history as a wellspring for organized crime — and surprised younger residents with no knowledge of that past in what is now regarded as one of the world's safest cities.