LONDON (AP) — The Latest on the death of 39 people in a truck container in southeastern England (all times local):

11:45 a.m.

Essex police say they have not yet identified the 39 victims found dead in a truck container or established where they came from.

Deputy police chief Pippa Mills said identifying the victims "could be a lengthy process" and that a key line of inquiry will be how the truck entered Ireland. The truck is said to have entered Britain via the Welsh port of Holyhead on Saturday from Ireland.

"It is an absolute tragedy and a very sad day," Mills said.

Mills did not detail how many of the deceased were men or women, but confirmed that one of those who died appeared to be a teenager.

9:50 a.m.

Police in southeastern England say 39 people were found dead in a truck container believed to have come from Bulgaria.

A 25-year-old-man from Northern Ireland has been arrested on suspicion of murder.

Chief Superintendent Andrew Mariner said Wednesday that authorities are in the process of trying to identify the 38 adults and one teenager.

Mariner says the truck entered the country on Saturday, Oct. 19 and that police were "working closely with our partners to investigate."

A cordon has been put in place around Waterglade Industrial Park in Thurrock, which remains closed.