The deep canyons and craggy rocks of the Santa Monica Mountains hold many mysteries. People vanish in the vast urban wilderness. Sometimes they turn up dead.

For the fourth time in as many months—and as local residents talked in hush tones about the crime-filled summer that they’ve seen unfold—Los Angeles County sheriff’s detectives were called into the local hills to investigate the discovery of yet another corpse.

A Caltrans worker found human skeletal remains Sept. 5 on the Juan Bautista de Anza East Trailhead in Calabasas. The trail is in the 25100 block of Calabasas Road about one mile north of Mureau Road.

The Los Angeles County Department of Medical Examiner- Coroner confirmed that the body is human. The remains, which are said to be those of a male, could be up to 6 months old, an official said. Due to the level of decomposition, the cause of death was not readily apparent.

Calabasas City Manager Gary Lysik said that Capt. Josh Thai of the Lost Hills Sheriff’s Station informed him of the situation.

“There was absolutely no evidence of any wrongdoing, no weapons found, anything. They’re not calling this a homicide,” Lysik said. “They believe they know who it is, but the name is being withheld until other family members are notified.”

Detectives were called to the Malibu Canyon area south of Calabasas after passers-by discovered dead bodies in May and July. Detectives said it was likely that a Los Angeles street gang went to the canyon to dump the victims.

The body of 52-year-old Francisco Reynaldo Cruz was found May 16 in a drainage ditch along the 1600 block of Las Virgenes Canyon Road south of Calabasas. Cruz was killed by sharp force injuries to the neck and chest, and a blunt force injury to the head, a report said.

The body of 19-year-old Roger Eli Chavez-Barahona was discovered on an embankment next to Piuma Canyon Road on July 27. He died from multiple gunshot wounds, the L.A. County coroner said.

On June 22, Irvine resident Tristan Beaudette was shot and killed while camping at Malibu Creek State Park. Since then, there have been nine reports of gunfire in the canyon, but none of the incidents have been confirmed as gunshots.

At a public safety meeting hosted by state Sen. Henry Stern last month, Lt. James Royal of the Lost Hills Sheriff’s Station said that, after investigation, several reported “gunshots” turned out to be cars backfiring, an exploding transformer and, in one case, a windshield shattering due to heat.

Regardless, reports of gunfire spread through social media, and some residents have become wary of going hiking and camping in the area.

“When we were at the scene, there was discussion like, ‘the public is saying shootings, this, that and the other.’That one shooting that did take place is all that the sheriff knows about,” Lysik said. “Everything else was fireworks or a transformer that made some noise, a car backfired.”

Dark secrets

Still unsolved is the disappearance of Timothy Perryman, a 53-year-old Agoura Hills man who went hiking in the local mountains in 2004 and was not seen again.

In 2009, 24-year-old Mitrice Richardson was taken into custody by the Lost Hills Sheriff’s Department for an infraction and went missing right after her release from the Calabasas jail.

Her remains were discovered the following year in the remote mountain area of Monte Nido; a cause of death was never determined.

In another case, this one in 2017, 20-year old Glendale resident Elaine Park was seen leaving in a car from the home of an ex-boyfriend in Calabasas.

The car was found five days later on the other side of the mountain near Corral Canyon. Inside the unlocked car, with keys still in the ignition, were Park’s backpack, cellphone, computer and cash. The woman hasn’t been seen since.

Questions also remain in the case involving Matthew Weaver Jr., who disappeared a month ago.

A car belonging to the 21-year-old Simi Valley native was found abandoned in the Topanga Canyon area of the Santa Monica Mountains on Aug. 11.

Weaver was last seen Aug. 10 in the 2600 block of Stearns Street in Simi Valley, the Los Angeles Police Department told the Acorn. His car was found the next day near the Rosas Overlook above the Backbone Trail and Hondo Canyon.

Malibu Search and Rescue conducted several searches for the missing man but nothing turned up.

Weaver’s family questions whether the summer’s shootings and dead bodies might have a connection. Sheriff’s investigators so far have said no.

Anyone with information about the cases, including the Sept. 5 discovery, is asked to call the Los Angeles County Sheriff’s Department’s homicide bureau at (323) 890-5500.

John Loesing and Stephanie Bertholdo contributed to this article.