The body of a 6-year-old boy with autism was found in a dumpster at his Lynnwood apartment building on Tuesday. The Snohomish County Sheriff's Office reports his 19-year-old relative admitted to drowning him in a bathtub, putting him in a box and then throwing him in a dumpster.

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Dayvid Pakko's disappearance 

The boy, Dayvid Pakko, was reported missing at about 5 p.m. Monday.

Crews, including 100 volunteers, searched the area of 44th Avenue West between 156th Street and State Route 99, just outside the Lynnwood city limits.

According to the sheriff’s office and relatives, Dayvid stayed home sick from school Monday.

The boy lived with his mother, who was at work when he disappeared. He was last seen at about 2:30 p.m. The sheriff's office said Dayvid was under adult supervision while he was at home, but did not say who he was with.

The Snohomish County Sheriff’s Office said there was evidence that Dayvid was a victim of homicide.

The 'tragic ending to a long search operation' 

Authorities said the body was found in a dumpster at the Bristol Square Apartment complex on 44th Avenue West at about 2 a.m. Tuesday.

"It's a tragic ending to a long search operation," said sheriff's office spokeswoman Shari Ireton.

The body was found by officers with the violent offender task force. In cases of missing children, the officers, who represent several law enforcement agencies, are deployed to check on registered sex offenders in the area.

Detectives processed the crime scene for hours on Tuesday. Once a search warrant is obtained, detectives will go through the apartment building and dumpster for evidence.

Arrest of 19-year-old relative 

A 19-year-old man visiting family in Lynnwood from Kerrville, Texas, was arrested Tuesday and charged with first-degree murder in connection to Dayvid’s death.

KIRO7.com found that a man named Andrew Henckel was booked into Snohomish County Jail on suspicion of first-degree murder. Henckel shares the same last name as the victim's mother, and he was visiting from Texas.

According to the sheriff's office, the 19-year-old admitted to filling a bathtub with water with the intention of drowning Dayvid. He called the boy to the bathroom, picked him up and placed him face down in the water, according to authorities.

The 19-year-old reportedly held the boy's head underneath water for approximately 30 seconds before Dayvid became still. He was left face down in the water for nearly six minutes, according to authorities. The 19-year-old wrapped the boy's body in a blanket and placed him in a cardboard box, which he used to dispose of the body in the nearest garbage dumpster.

The Snohomish County medical examiner will determine the boy's cause of death.

Community holds vigil 

By Tuesday evening, dozens of people had dropped off candles, balloons, notes and flowers at a memorial for Dayvid outside Bristol Square Apartments. Samantha Burden's 8-year-old son Kaedyn was friends with the victim.

"We used to wrestle and play," Kaedyn said.

Burden said the kids often played together on the playground.

"Just thinking about what (Dayvid) went through, it's just disgusting," she said.

Phillip Edwards, a friend of the Pakko family, describes the child as an energetic, sweet boy.

"He loved Legos, he was brilliant. Smart as a whip," Edwards says, "I don't understand why a person could go through such lengths with such a small child."

Gabriela Moore, a postal worker, lives nearby and watched helicopters fly over the apartment complex Monday, when investigators thought Dayvid was missing. Investigators said the child was mildly autistic.

"It's not your child but it hits home," Moore says, "There's no words. There really is no words."

Creekside Church also held a vigil for Dayvid at the Mountlake Terrace campus Tuesday evening.