One person is dead after what is believed to be a string of drug overdoses at Maplehurst Correctional Complex in Milton, Ont. Tuesday night, Halton Police confirm.

Police were called to the jail around 6 p.m. for reports that multiple inmates needed medical attention. Six were taken to hospital, of which one died, Staff Sgt. Jeff Foster told CBC News.

Foster said all of the inmates involved had been confined to the same cell block and that an illegal drug was involved.

It's unclear how the drug made its way into the jail, he said.

Police have not said what type of drug was used or how, but say the criminal investigation bureau and jail staff are investigating, along with the province's coroner.

In a statement, the province's Ministry of Community Safety and Correctional Services would not confirm the overdoses, saying only that six inmates were found in "medical distress" and that staff performed first aid before paramedics arrived.

"It is not appropriate for the ministry to comment further as a number of investigations are underway," spokesperson Andrew Morrison said in a statement.

Should the coroner find the death was not the result of natural causes, a mandatory inquest will be called.