A 14-year-old boy was found naked and dead in a culvert in Northern Ireland in June 2020

This week, an expert said at an inquest into his death that it was likely that he had entered the storm drain alive

“The quadrant would fill with water relatively quickly,” Professor Carolyn Roberts said

Almost six years after a missing 14-year-old was found naked and dead in a storm drain in Northern Ireland, an expert said it was likely that he had entered the space alive.

This week, Professor Carolyn Roberts spoke at an inquest into Noah Donohoe’s death and revealed that the teen likely entered the culvert by squeezing through the “vertical metal bars” before he was found dead in June 2020, U.K. outlets the BBC and The Independent reported.

“The bars of the grille are sufficiently widely spaced that a large child or even a small man could deliberately climb through without undue effort,” Roberts said in her report that was commissioned by the Coroners Service for Northern Ireland and presented at Belfast Coroner’s Court, according to The Independent.

On June 21, 2020, Donohoe left his home in Belfast on his bicycle around 5:40 p.m. local time and was reported missing. His body was discovered six days later, according to Ireland's national public service broadcaster, Raidió Teilifís Eireann (RTÉ).

An autopsy has since revealed his cause of death as drowning, the outlet reported.

The layout of the storm drain was "relatively complex and for an unfamiliar person moving in semi-darkness, in my opinion, it would appear possible to become disoriented,” Roberts told the court, according to the BBC.

After visiting the site herself, the professor determined that the culvert most likely would have experienced high tide that June night, after the 14-year-old entered the drain system, between 11:30 p.m. and midnight.

“This is some five or six hours after his last sighting, which would allow adequate time for him to have made his way several hundred metres along the culvert," she told the court, according to The Independent.

“At this point, water is likely to have risen almost completely to fill the culvert around and immediately above the point at which the boy’s body was discovered, creating conditions for drowning,” Roberts said.

“The quadrant would fill with water relatively quickly,” the expert continued, according to the outlet, “and in darkness with a complex network of pipes and cold conditions, the boy would be likely to have become confused, in my opinion.”

While there’s a possibility that Donohoe could have survived for multiple tidal cycles, the temperature in the storm drain “would not be conducive to this with a naked body in my opinion,” she told the court, The Independent reported.

Roberts said it was likely that the teen entered the storm drain in the late afternoon of June 21, 2020, and crawled or walked about 2,000 feet before he drowned, the outlets reported.

Other experts also spoke about whether a screen should have been installed, according to the reports. Dr. Mark Cooper told the hearing that “the decision not to have a security screen is crucial to this case,” the BBC reported.

Earlier this year, the child’s mother, Fiona Donohoe, described the period between reporting Noah missing and his body being found as a "living nightmare," in video footage played in court, according to The Guardian.

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In the week before his disappearance, she’d also been increasingly concerned about his mental health.

"I miss every detail of my beautiful darling Noah," she said in the video, according to RTÉ.

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