VICTORVILLE, Calif. (AP) — Officials say foul play is suspected in the deaths of two inmates at a federal prison in Southern California, which is on lockdown as an investigation proceeds.

Prison spokesman James Engleman said Sunday in a printed statement that the inmates died late Saturday and that the FBI is investigating their deaths as homicides.

No prison workers were harmed.

All inmates are on lockdown at the facility housing 1,300 prisoners. The prison is one of four facilities at a federal correctional complex in Victorville, about 80 miles northeast of Los Angeles.

FBI spokeswoman Laura Eimiller said she could not comment further.

The inmates’ names won’t be released until their families can be notified.

Prison officials say no further information will be released over the weekend.

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