Detectives searching pop singer Justin Bieber’s Los Angeles mansion over an egg-throwing attack seized cocaine and arrested one of the singer’s associates on Tuesday, officials said.

Los Angeles Sheriff’s Department officer Dave Thompson said an individual was arrested after drugs were discovered in “plain view” as deputies combed through Bieber’s luxury home in the upmarket enclave of Calabasas.

Around a dozen detectives swooped on the 19-year-old star’s home early Tuesday, probing allegations that the Canadian teen idol was responsible for causing thousands of dollars in damage to a neighbour’s house after pelting it with eggs.

Thompson said an investigation into a “felony crime” was ongoing.  He said cocaine found at Bieber’s property was “in plain view of the deputies when they were looking for the evidence.”

Bieber, who was in the home during the raid, had been neither “arrested nor exonerated” in connection with the vandalism case, Thompson said.

He added that the pop star was “not connected to that cocaine other than the gentleman was staying at his residence.”

Officials however dismissed suggestions that the nature of the alleged vandalism - alleged to have caused as much as $20,000 in damage - was trivial.

“A felony crime is a felony crime. The damage was from the eggs,” Thompson added.

“The felony comes from the amount of the damage, and this residence sustained a great amount of damage that easily achieve the felony vandalism section.”