Police have raided 20 homes on a notorious London council estate and arrested 17 people in a crack-down on the trade in drugs and illegal firearms.

At 4am this morning, about 500 officers swooped on the South Kilburn Estate in north-west London.

The raid targeted criminals seen by local residents as "untouchable", said Detective Chief Superintendent Barry Norman, who led the operation.

South Kilburn is a hotbed of gun crime in the borough of Brent. In July 2005, the 20-year-old Junior Ogie was shot dead in a daylight gang fight in front of at least 12 people on the estate.

Police knew who the killer was, but despite a £20,000 reward it took more than a year for named witnesses to step forward - leading to an arrest last November.

The crack house robber Joel Smith, jailed for gunning down six-year-old Toni-Ann Byfield after she saw him murder her drug dealer father Bertram, also lived on the estate.

In today's raids detectives seized more than two kilograms of cocaine and several stolen cars.

They also recovered five firearms, a silencer, ammunition, cash and credit cards.

"No one is untouchable," said Det Ch Insp Norman. "We will continue to target prolific offenders involved in drug dealing, firearms and other criminality."

The 17 arrests made today, which includes two women, were prompted by tip-offs from the community to the local safer neighbourhood police team.

The raids were the result of a "lengthy intelligence-led operation" targeting firearms offences, drug dealing and the handling of stolen goods and vehicles, Det Ch Insp Norman added.

"We cannot allow people perceived to be successful through their criminality, to have a negative impact on our communities, in particular, young people."