SINGAPORE - Gangsters once roamed Singapore streets armed with guns and parangs. They extorted money and thought nothing of starting a shoot-out with police officers.

It was during those days that Mr Au-Yong Weng Wah joined the police force - in 1953 - and climbed the rungs to become head of the Secret Societies Branch in the Criminal Investigation Department (CID).

In that position, he played a significant role in ridding the city of dangerous and powerful gangs. In his 32-year career, he was also involved in handling the 1964 racial riots, Hock Lee bus riots and a high-profile robbery of 120 gold bars when three men were murdered.

Deputy Assistant Commissioner Au-Yong retired from the force in 1985, as director of public relations.

On June 29, he died at the age of 86, after battling a rare blood cancer called myeloma for 13 years.

He leaves his wife, Ms Rosine Kee, and three children.

Among those who turned up for his wake held at Pine Grove, off Holland Road, were former police commissioner Tee Tua Ba and former CID director Tan Eng Bock. Members of Parliament for Holland -Bukit Timah GRC Sim Ann and Liang Eng Hwa also turned up.

Mr Tee, who was once Mr Au-Yong's subordinate, told The Straits Times at the wake on June 30: "He was a very good mentor, very open, straightforward. He was strict, but gentle, friendly."

Many of Mr Au-Yong's veteran colleagues echoed the sentiments, saying he was generous, paying for their meals out of his own pocket. Some penned tributes on Facebook.

One of them, Mr Sukhdev Singh Gill, 66, wrote of his experience attending to a robbery at a location rife with gangsters. Mr Au-Yong, his superior at the former Paya Lebar police station, attended the case with him in full uniform.

"He instilled fear in the gangsters of that area for he was much feared by the underworld then. That incident of leading by example made me admire and respect this great officer," he said.

In fact, it was not only fear he instilled in these gangsters, said his son, Kenneth, 55, a lawyer. "He was very well respected. When we met some of these ex-gangsters years later, they had become successful businessmen. They would greet him and thank him for the chance to turn over a new leaf," he said.

At home, his father was every bit the disciplinarian, and did not take well to playfulness, the younger Mr Au-Yong said.

He was protective, but did not pamper, and was always concerned about the family even in his final days, he said.

The veteran, once known for his booming voice and active lifestyle, was hospitalised for eight days before he died.

Mr Kenneth Au-Yong said: "We knew this day would come... I'm sad, but relieved that his suffering has ended."