08/21/2015 19:30 EDT | Updated 08/21/2016 01:12 EDT

Alberta prisoner dies after overdose, four others sent to hospital

EDMONTON — One of five inmates who overdosed this week in an Alberta prison has died.

Ryan William Witvoet, who was 31, was found unresponsive in a cell at the maximum-security Edmonton Institution on Thursday.

Officials have yet to determine the cause of his death or what drug the prisoners ingested.

Acting deputy warden Mark Otto says officials aren't ruling out fentanyl, a drug that has killed hundreds of Canadians in the last few years

Otto says one inmate who overdosed remains in hospital in stable condition.

Three others were treated in hospital and returned to the prison.

Witvoet has been serving a six-year sentence for various crimes, including property, weapons and driving offences.

The Canadian Press