Deputies were investigating claims made Tuesday by a neighbor that Justin Bieber attacked and threatened him during an argument in suburban Los Angeles, authorities said.
No one was arrested and few details were immediately available.
A representative of Bieber did not immediately return a request for comment.
Online schedules indicate the "Baby" singer is in the midst of a European tour and performed a show in Poland on Monday night.
Los Angeles County Sherriff's Department spokesman Steve Whitmore says authorities were called to the scene in Calabasas just after 9 a.m. Tuesday.
"There have been allegations made against Mr. Bieber of battery and making threats," Whitmore said. It's unclear who called authorities, and whether there have been previous complaints about problems between the 19-year-old crooner and neighbors.
The first leg of Bieber's european concert tour has been marked by reported outburts and odd behavior from the star.
As recently as Monday night, Bieber chose to enter and proceed through an airport shirtless after performing to a sold out venue in Poland. "He wasn't told to take off his clothes. He had no metal objects on him." a spokeswoman for Lodz Airport in central Poland told Reuters. "He's quite skinny so I assume he was probably freezing."
While in London in early March, he was photographed wearing a gas mask in public and lashed out verbally at a paparrazi on the street. The singer performed four concerts while in British capital and turned up to one show two hours late after citing "technical issues." During another he appeared faint while onstage and had to receive treatment backstage before resuming the performance. He was admitted to hospital that night - and tweeted a shirtless picture of himself to fans while under observation - but was later released.
Bieber is next scheduled to perform in Munich, Germany on March 28.
The investigation was first reported by TMZ.com.
Copyright Associated Press/NBC