Queensland police have concluded the child’s body found on the Papua New Guinea mainland is unlikely to belong to one of five people missing from an empty boat found floating in the Torres Strait.

Two men, two women and a nine-year-old boy set off from Badu Island for Dauan Island on 31 July, but never arrived.

“Investigations indicate that it is highly unlikely that a child’s body located near Old Mawatta Village on mainland Papua New Guinea on August 2 is that of the missing nine-year-old boy,” police said in a statement.

The five’s empty boat, a seven-metre vessel, was found on Friday afternoon about 4.5km west of Dauan Island.

Papua New Guinea authorities found a child’s body near Old Mawatta Village on the mainland.

Queensland police said the child’s body was found outside the search area.

On Sunday afternoon police advised the families of the five missing people in the Torres Strait that there was little chance of finding the group alive after a four-day air and sea search failed to locate them.

Chief Superintendent Brian Huxley said Queensland police located life jackets and an EPIRB from the boat “but regrettably, we’ve not been able to find the people in it”.

“We’ve [now] delivered the terrible news to the families that we’ve been unable to find their loved ones,” he said on Sunday from the Torres Strait.

“It’s incredibly sad news not just for Dauan Island [but for] Saibai and the entire community up here in the Torres Strait.”

Huxley said rescuers conducted an extensive air and sea search operation covering thousands of square kilometres.