"Detectives from Rancho are conducting a death investigation," said sheriff's spokeswoman Jodi Miller. "She's a deceased female and no foul play is suspected."
Lt. Mike Keltner, a watch commander for the Pomona Police Department, said the chief of police Dave Keetle would be releasing a statement and no other information will be given out.
"This is still under investigation," Keltner said. "We wouldn't want to compromise the Sheriff's Department's case."
Miller said that this is being looked at as a suicide, but couldn't release any more information at this time.
The officer's name will be withheld pending notification of her next-of-kin.
Authorities are asking for any information be directed to sheriff's homicide bureau at 909-387-3589.
Reach Dougvia email, call him at 909-386-3925, or find him on Twitter @crimeshutterbug.
Get the latest crime and public safety news on Twitter @IECrime.