SYDNEY, March 14 (Xinhua) -- A total of 21 people were arrested by Australia's Victoria police in a series of raids across Melbourne targeting bikie gangs on Tuesday morning.

A spokesperson for Victoria Police said that drugs and cash were seized in the raids on 26 residential and commercial properties with links to the Comancheros motorcycle gang at 5 a.m. local time.

The raids were part of an operation which began in July 2016 that was investigating the firebombing of Kittens, a nightclub in Melbourne's south-east early in 2016, in addition to a host of other gang-related incidents

"We believe that they are responsible for 21 non-fatal shootings, four arson attacks and serious drug trafficking and firearm related offences," Stephen Fontana, Victoria Police assistant commissioner, told reporters on Tuesday.

"Some stem back to firebombs on Kittens Nightclub in the South Melbourne area.

"As a result of today's operation, it's anticipated up to 21 individuals will be interviewed and charged with serious offences including drug trafficking, criminal damage by fire and a number of drive-by shootings causing injury to others."

The raids were carried out by the Echo Taskforce which was established in 2011 to combat notorious bikie gangs such as the Comancheros.

Doug Fryer, another assistant commissioner, said the raids proved that Victoria would not tolerate criminal activity of the "gangsters in colors."

Police smashed a window and broke a security door at a property in Lyndhurst, south-east of Melbourne's CBD, where two high-end cars were seized.

Neighbor Stephen van Duynhoven told reporters that a man lived in the property with his girlfriend.

"He's a really nice guy, nice girlfriend," Duynhoven told reporters.

He said police had visited the property constantly.

"About three times in the last five, six weeks and that's probably why we didn't think much of it," he said.