Two American DJs caused panic when they falsely reported that Britney Spears and boyfriend Justin Timberlake had been killed in a Los Angeles car crash.
Kramer & Twitch broadcast the news on Dallas rock station KEGL-FM.
Hundreds of listeners and distraught fans jammed police and fire service numbers and local hospitals.
The LA Fire Department had to put a telephone voice message on their answerphone saying they had "no knowledge of a well-known singer and her boyfriend" being involved in an accident.
Representatives of Spears, 19, and Timberlake, 20, a singer with the band 'N Sync, could not be contacted and the station refused to comment.
Jason Lee, of the LA Police Department, said he got 50 to 75 calls in a matter of hours. Brian Humphrey, a spokesman for the Fire Department, received more than 100 calls from all over the globe.
The California Highway Patrol and local hospitals also received calls, reports said.
The Addicted to Britney Spears Support Group website carried messages from distraught fans.
One said, "I heard here on a Dallas, Texas, radio station that Britney Spears died in a car accident. Anyone else hear anything?"
It is not the first time Kramer and Twitch have been involved in a controversial report.
In a hoax involving Britney last June, radio stations said she would appear in Wilkes-Barre, Pennsylvania.