SANTA BARBARA ( – Investigators returned Saturday to the Lake Cachuma area in Santa Barbara County to search for evidence related to the disappearance of a 5-year-old South Pasadena boy who has been missing since April.

Aramazd Andressian Jr. was last was seen the evening of April 20 at Disneyland in the custody of his father, Aramazd Andressian Sr., who was found unconscious at Arroyo Seco Park in South Pasadena two days later and was unable to account for his son’s whereabouts.

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Authorities searched the Lake Cachuma Recreation Area on April 25 after a witness reported seeing the boy with his father there on April 21.

According to a sheriff’s department statement Friday, detectives have examined evidence that indicates that in addition to spending April 21 visiting the Lake Cachuma Recreation Area, the father traveled around the area near Solvang and Nojoqui Falls.

RELATED: The latest on the search for Aramazd Andressian Jr.

The search for Andressian has spanned several Southern California counties.

The elder Andressian was jailed for three days on $10 million bail before being released. He told investigators he had arrived at the park with his son and waited for the golf course to open, and admitted ingesting prescription medication that was not prescribed to him, Los Angeles County sheriff’s Lt. Joe Mendoza has said.

The father said he did not remember what happened to his child or any details that were useful in locating the boy, according to Mendoza, who said a prescription bottle was found inside Andressian’s vehicle, which was doused with gasoline inside and out.

Andressian was in the middle of a divorce and custody battle with the boy’s mother, Ana Estevez, who investigators have said is not a suspect in the child’s disappearance.

Search dogs and detectives from the Sheriff’s Homicide Bureau were on hand, along with personnel from the Santa Barbara County Sheriff’s Department, the Los Angeles County Fire Department, the South Pasadena Police Department and partner agencies from throughout the San Gabriel Valley.

The boy’s mother says she hasn’t given up hope that her son will be found alive.

Detectives served a warrant at the Montebello home of the boy’s paternal grandmother on May 25. The boy’s father had reportedly recently moved into the home, where investigators “seized various items of evidence,” according to a sheriff’s statement released at the time. Other details were not disclosed.

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Authorities conducted another search of the park on May 18 after receiving what they said was a “credible” tip, but did not find any evidence. The search was in the same general area that was scoured by South Pasadena and San Marino police soon after the boy went missing.

On April 28, the day a search warrant was served at his South Pasadena home, Andressian released a statement through his attorney about his son’s disappearance, his only public statement.

“I hope and pray for the safe return of my only child, my namesake, who has been missing since last Saturday morning, April 22nd,” he said then.

The elder Andressian said he and his family “are heartbroken and grief- stricken that Aramazd Jr. is missing and may be in harm’s way.”

“I am pleading with the public to come forward with any knowledge of Aramazd Jr.’s whereabouts or information regarding the circumstances leading up to his disappearance,” he said.

The boy’s mother contacted police at 9 a.m. April 22 to report her son missing. She said her estranged husband had failed to drop off the child at a pre-arranged meeting place.

A $20,000 reward has been offered by the Los Angeles County Board of Supervisors for information that helps authorities locate the child, who is white, 4-foot-1 and 55 pounds, with brown hair and brown eyes and a small mole on the bottom of his right shoulder.

LA County Sheriff’s Altadena Mountain Rescue Team, Special Enforcement Bureau and several LA County search and rescue teams assisted with today’s search, authorities said.

It was unclear what led authorities to resume their search in the area.

Anyone with information on the case was urged to call homicide detectives at (323) 890-5500. Anonymous tips can be submitted through Crime Stoppers by calling (800) 222-TIPS.

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