Gardaí have launched an investigation into what happened to a young boy living in Dublin who appears to have vanished without being reported missing.

An investigation team is trying to determine if the boy, aged three to four years when last seen, died in suspicious circumstances without the authorities being notified or any concerns being flagged.

The Irish Times understands gardaí have spoken to the parents of the child, one of whom is abroad and one who remains in Ireland. Both are Irish citizens.

Two possibilities are being explored: that the child was unlawfully killed or that he died of natural causes. However, the resources of a homicide inquiry have been committed to the case in the event his death was unlawful.

Garda sources also said that, irrespective of the circumstances, concealing a person’s death, and the secret burial of human remains, were criminal offences.

The investigation team is considering several pieces of information, including some they hope may lead them to the remains of the child, who would be aged eight if still alive.

Though the next steps in the inquiry remained fluid on Monday night, a search and excavation operation was expected imminently and may begin as early as Tuesday.

A property in north Co Dublin was sealed off over the weekend.

A person of interest, spoken to by the Garda investigation team, has made claims about a third party in relation to the boy’s apparent death, possibly four to five years ago.

It is understand the boy’s disappearance came to light when social welfare payments related to him were being claimed. No proof the boy was alive was provided and there was no record of him having attended school.

The alarm was raised with gardaí last Friday by Tusla, the child and family agency, with a missing persons inquiry launched immediately.

The Garda investigation team has also spoken to a number of other people they believe knew the child. An incident room has been set up at Swords Garda station.

A woman was interviewed about the boy, amid grave concerns for him, and during those interviews she claimed he had been killed by another person.

Though the claims made by the woman during Garda interviews have not been proven, gardaí are taking them seriously.

In a statement, Tusla confirmed it made a referral to An Garda Síochána “in relation to our concerns about the safety and wellbeing of this child”.

“We continue to work closely with the Garda and, in line with normal practice, all relevant information relating to this family has been shared.”

Garda headquarters also confirmed an investigation had commenced, in the case first reported by the Irish Mirror on Monday.

“Gardaí are continuing to carry out operational enquiries in north Co Dublin into the current whereabouts and welfare of a child,” it said.

In a statement, Minister for Children Norma Foley said she had been briefed by officials and had spoken to the Tusla chief executive.

“I am deeply concerned about this missing child. Uppermost in my thoughts is the welfare of this child,” she said, appealing for anyone with information to provide it to An Garda Síochána.

Tusla reported its concerns about the child to the Garda last Friday, exactly one year after it reported concerns about the welfare of Co Louth boy Kyran Durnin. Kyran was six years old when he was last seen alive in mid-2022 and gardaí believe he was killed and his remains disposed of in a bid to conceal the crime.

However, though there are fears the boy who lived in Dublin may also have been killed in a concealed death, his case is not linked in any way to that of Kyran Durnin.