A 5-year-old boy with autism was found dead Friday morning after leaving his family’s apartment in Hillsborough County, Florida, and entering a nearby retention pond, authorities said.

The child was discovered in the water just a short distance from the apartment complex after his family realized he was missing.

According to authorities, the boy’s father said he last saw his son around 5 a.m. while they were sharing a bed. When the father woke again around 9 a.m., the child was no longer there.

The father immediately contacted authorities, prompting the Hillsborough County Sheriff’s Office to launch a large-scale search.

More than 140 units joined the operation, including members of the sheriff’s Drone Team, Aviation Unit, K-9 Unit, and Dive Team. After several hours of searching, the boy was found in the retention pond shortly after 11 a.m. He was pronounced dead at the scene.

Hillsborough County Sheriff Chad Chronister described the death as the family’s “worst day” and expressed condolences to those who knew the child.

“There are no words that can ease the pain of losing a child,” Chronister said.

He added that deputies and investigators involved in the search had hoped to bring the boy home safely and were deeply affected by the outcome.

The tragedy has also drawn attention because authorities said it was the second time in less than two months that an autistic child had been found dead in a pond at the same apartment complex.

The latest case remains under investigation as authorities work to determine the circumstances surrounding the child’s death.

For the family, however, the search that began with hope ended in an unimaginable loss. A morning that started like any other became a devastating day they will never forget.