Alleged underworld boss Cyril Beeka was gunned down in what appears to have been an assassination in Cape Town Monday night.

Cape Town police were hesitant about giving details of the shooting, shortly after 5pm in Modderdam Road, Belville, but they have confirmed that gunmen opened fire on the vehicle in which Beeka, 49, a security company owner, and his unnamed driver were travelling.

Police spokesman Captain Joe Wilson said Beeka's car, a BMW X5, was travelling west when the shooting occurred.

"Two guys drove by on a motorcycle and fired several shots at the car. The driver lost control and smashed into a light pole and [the car] eventually landed on its side 100m from where the shooting happened."

Wilson said the 36-year-old driver was seriously injured and that Beeka died on the scene. The driver was airlifted to Vincent Pallotti Hospital in a critical condition.

Wilson said witnesses have been identified. No arrests have been made.

Beeka's brother, Daniel, who rushed to the scene, close to the entrance to the University of Western Cape, said he had sketchy information but was told that Beeka sustained a fatal shot to the chest.

Beeka said his brother was on his way to visit him .

"Naturally, we are shocked ... I thought by the time I got to the scene he would still be alive."

Beeka said he had no reason to believe that his brother had concerns for his life, though there was talk that Cyril Beeka told a close friend about a week ago that he feared harm.

"He was a businessman. He was not living in fear and was going about life as usual."

Beeka's wife was in Johannesburg and he is survived by four children, his brother said.

Beeka was no stranger to controversy and was said to be a key figure behind protection rackets in Cape Town. He has been linked to alleged underworld figures, including reputed gangster Yuri Ulianitski, convicted druglord Glenn Agliotti and Czech fugitive Radovan Krejcir.

In 2007, Beeka - said to have been a member of uMkonto weSizwe - accompanied ANC notable Moe Shaik to the party's Polokwane national conference, creating considerable controversy.

Over the years, he has been linked to drug trafficking, extortion, money laundering, assault, forgery and murder.