SAN FRANCISCO (CBS SF) — Police say a homeless trio wandering the San Francisco Bay Area used a handgun stolen from an unlocked car to rob and shoot to death two people.

San Francisco Police Lt. Toney Chaplin said the handgun was reported stolen on Oct. 1 from the Fisherman’s Wharf neighborhood in San Francisco.

Audrey Carey, a 23-year-old resident of Quebec, Canada, was found dead two days later in Golden Gate Park. Carey was shot in the head.

The body of 67-year-old Steve Carter was found Monday in the Loma Alta Open Space Preserve in Marin County.

The three young people were arrested in Portland, Oregon, on Wednesday and are expected to return to the Bay Area, first to Marin County and then to San Francisco, to face homicide charges.

Police say the suspected murder weapon was recovered during the arrest.

The three will be charged with Carey’s robbery and murder, as well as that of Carter, according to police.

San Francisco police said the suspects, identified as Sean Michael Angold, 24, Morrison Haze Lampley, 23, and Lila Scott Alligood, 18, were arrested at a dining hall around 2:15 p.m. Wednesday in Portland, but that more information about their backgrounds has not yet been made public.

Carey was found lying face down near the bison paddock in Golden Gate Park by a passerby around 9 a.m. on Saturday. Carter was found dead of multiple gunshot wounds by a hiker on a trail just after 6 p.m. on Monday.

Carter’s dog, a Doberman Pinscher, had also been shot and was still leashed to him, according to the Marin County Sheriff’s Office.

Carter’s Volkswagen Jetta was missing and investigators then found surveillance footage showing three people refueling the Jetta at a gas station in Point Reyes Station.

Investigators were able to use the car’s GPS to track it to Portland, where the trio was arrested at the dining hall, sheriff’s officials said.

San Francisco police contacted Marin County investigators after learning of Carter’s murder due to the fact that both victims were fatally shot in wooded or park areas.

Following the arrest of the trio in Portland, San Francisco detectives flew to Portland and discovered that Carey’s property had been found in the suspects’ possession, San Francisco police spokesman Officer Albie Esparza said.

Marin County sheriff’s Lt. Doug Pittman said it does not appear that Carter knew the suspects and investigators do not know why they shot him.

Carter and his wife, Lokita Carter, founded the Lake County-based Ecstatic Living Institute in 1999 to teach subjects such as tantric massage and yoga.

Lokita Carter keeps a blog about her battle with breast cancer and wrote this week that she is deeply appreciative of the outpouring of support following her husband’s death.

“I am beyond words, and it is only the knowledge (of) how much you all love Steve, and me, that keeps me going at this extremely difficult time,” she wrote.

Police have not said what items were stolen from the homicide victims or whether the suspects were in an altered mental state during the homicides.

Homicide investigators are expected to release additional information about the homicides this afternoon, according to San Francisco police.

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