TIJUANA, Mexico (AP) — A 3-year-old boy who fell into an open manhole in Tijuana, Mexico, has been found dead in the sewer system miles from where he disappeared.

U-T San Diego reports Ivan Alexander Sanchez's body was recovered Wednesday about 2 1/2 miles (3.2 kilometers) from where the accident occurred Sunday morning.

There's no word on the cause of death, but authorities have said the boy's 10-foot (3-meter) fall, noxious gases and a lack of oxygen in the sewer pipelines made his survival unlikely.

The boy's family was walking to a park when he fell through the hole.

Crews spent three days searching miles of sewer and storm drains and even checked a sewage treatment plant across the U.S. border.

Tijuana has been struggling with the theft of manhole covers to sell as scrap.

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