(CNN) -- An improvised explosive device went off inside a federal prison in California during a search Saturday, according to federal authorities.
No one was injured, the authorities told CNN.
The incident happened in the recreation area of the Victorville Federal Penitentiary. Bureau of Prisons spokesperson Traci Billingsley said the device was found by a staff member during a "routine search of inmate property". She said it "detonated upon discovery."
A bomb squad from the San Bernardino County Sheriff's Department and FBI bomb technicians were called to the prison to examine the device and make sure it didn't pose any further danger. They remained inside the prison as of 9:30 p.m.
FBI spokeswoman Laura Eimiller said an investigation was under way. She said the incident is not terrorism-related.
Billingsley said the prison was locked down at the time the device was found. She could not say what prompted the lockdown, or if there was any connection to the search. No inmates were in the area when the explosion occurred.
"The prison remains secure," she said.
She said she could not recall a previous incident where an improvised explosive device was found inside a prison.
CNN's Steve Brusk and Kevin Bohn contributed to this report.