A felony drug arrest was made at the pop star's Calabasas mansion Tuesday; authorities say someone other than Justin Bieber was arrested.

Deputies searching Justin Bieber's Calabasas mansion Tuesday made a felony drug arrest of someone other than the pop star, authorities said.

The arrest came as authorities served a search warrant at Bieber's home seeking surveillance-video evidence to support allegations that the singer was involved in an egg-throwing incident last week that left his neighbor's home with an estimated $20,000 in damage, authorities said.

L.A. County Sheriff's Capt. Mike Parker did not immediately identify who was arrested, but he said it was not Bieber. Parker would not identify the drug involved.

Labeling Bieber a suspect in Thursday's egging incident, sheriff's officials served a felony search warrant looking for "video surveillance or other relevant evidence" in the case. 

Parker said the incident had been classified as a felony because the homeowner reported the value of the damage to his house at $20,000. "It is a very nice home with an expensive decor," he said.

Sheriff's spokesman Steve Whitmore said eight people, including the singer, were being detained inside Bieber's home during the search.

"They are being cooperative," Whitmore said. "We will seek to question Mr. Bieber in connection with a felony investigation."

Whitmore said it is common practice to temporarily detain people while a search warrant is being served.

The egging incident marks the latest clash between the pop star and his neighbors, who have accused him of throwing loud parties and speeding through the neighborhood.

In Thursday's incident, a neighbor called authorities, saying someone was pelting his home with eggs, said sheriff's Sgt. Dan Nagelmann of the Malibu/Lost Hills station. The neighbor was home with his daughter at the time, Nagelmann said.

Authorities said they didn't know what might have prompted the egging.

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