Fifteen children were taken to hospital Wednesday after taking morphine tablets at a party in Nipawin, Saskatchewan.

The children ranged in age from 11 to 15, said RCMP spokesperson Cpl. Brian Jones.

"All of the youths that became ill were taken to the Nipawin hospital, and from there, several of them were transferred to other area hospitals," said Jones.

Two are listed in serious condition, and three are considered stable. One child was treated and released, while the rest will remain in hospital.

Police say the morphine tablets belonged to a cancer patient who was out of town for treatment. The Tuesday night party took place at the patient's home.

The RCMP say no adults were present during the party.

Morphine is used to treat severe pain, and can cause nausea, vomiting, constipation, dizziness and sweating.

Dr. David Butler-Jones, Saskatchewan's former chief medical health officer, says morphine can be deadly.

"If you take a high enough dose of morphine, that it will suppress breathing, you stop breathing and then you die as a result," said Butler-Jones.

Nipawin has a population of 4,500. It's located about 150 kilometres northeast of Saskatoon.