The authorities have arrested on suspicion of murder one of the five people detained for questioning in connection with the death of a young boy found in a dumpster in the Los Angeles neighborhood of Panorama City, the Los Angeles Police Department said Wednesday.

The department’s juvenile division announced in a news release it has in custody “the suspect responsible for the murder of a child,” and said Brycson Gaddis, 20, was booked on suspicion of murder.

The release also identified the victim as 5-year-old Elyjiah Hearn, saying he was not Gaddis’ child.

ABC7-TV cited the boy’s grandfather as saying Gaddis used to be the boyfriend of Elyjiah’s mother and the couple had a violent relationship.

The LAPD said earlier in the day it detained a man and a woman at a Panorama City apartment complex Tuesday night after getting a tip. Officers were also seen taking custody of two children at the scene, close to where a vigil for Elyjiah was being held alongside an impromptu memorial.

A few hours later around 1 a.m., officers detained another two men and a woman while collecting evidence in the case at a unit in Hollywood, about 13 miles away.

According to multiple news reports, one of the five people was arrested on an unrelated charge, while the other three were released.

Elyjiah was found in a trash bin less than a mile from the apartment complex after police responded to a call on the morning of July 12. The LAPD said its Abused Child Unit took over the investigation.

At a police commission meeting Tuesday, LAPD Chief Jim McDonnell said the boy had signs of trauma, ABC7 reported.