SAN DIEGO — The quick reaction of a San Diego County Sheriff’s deputy may have saved a woman’s life on Thursday.

According to the sheriff’s department, deputies made contact with two women who were in a car that had an expired registration in the parking lot of the George Bailey Detention Facility in Otay Mesa.

Authorities say the woman told the deputies they were picking up property for someone and they both admitted they had been arrested before.

After a search of the vehicle, the sheriff’s department said a white substance was found inside one of the women’s purses that tested positive for fentanyl. The woman was arrested for possession of drugs on jail grounds, officials said.

While transporting her to the Las Colinas Detention and Reentry Facility in Santee just after 5:30 p.m., the sheriff’s department said a deputy noticed the woman was showing signs of a fentanyl overdose. Officials say the deputy pulled her patrol car over to check on the woman’s condition.

The in-custody woman admitted to the deputy she had taken fentanyl and may be overdosing, explained the sheriff’s department. At that time, authorities say the deputy turned on her patrol car’s emergency lights and sirens and began driving toward the closest hospital in Chula Vista.

The deputy noticed the woman’s symptoms were getting worse pulled over to administer a single dose of naloxone, or Narcan. This drug is used as a nasal spray that reverses and blocks the effects of opioids or narcotics in the body, officials said.

After the deputy gave the woman naloxone, she requested an ambulance to take the victim to the hospital. The sheriff’s department said paramedics arrived within minutes and rushed her to the Sharp Chula Vista Medical Center where she received treatment.

According the local authorities, all sheriff’s deputies have access to naloxone in the event that they need to administer the medication to someone experiencing an opioid overdose.

The condition of the woman, whose identity has not been released, is unknown at this time.