Thirteen people were treated for the effects of CS gas today after it was released during an attempted escape by a prison inmate who was being treated at Tallaght Hospital.
Gardaí said the man, a 60-year-old Belgian on remand in Clover Hill prison on drugs charges, was brought to the hospital A&E department this afternoon, complaining of chest pains.
It is understood the man demanded to be allowed to have a shower, and while unattended, took out the CS gas canister which he had hidden about his person.
He then sprayed it at the three prison officers who were guarding him, two of whom were injured.
Five patients and five visitors to the hospital were also sprayed with the gas, which causes serious irritation to the eyes and nasal passages. It can also cause breathing difficulties if inhaled.
The man was eventually restrained by gardaí and the prison officers.
An inquiry has begun into how the man came to be in possession of the gas canister.
Fine Gael's health spokeswoman, Ms Olivia Mitchell, demanded to know how the prisoner got hold of the gas.
"To the best of my knowledge this is not something you can pick up at the local supermarket," she said. " Normally, only the security forces have access to a product such as this, and that it came into the possession of a prisoner would suggest a serious security lapse.
"Measures, which ensure the primacy of the safety of hospital personnel and patients must be put in place in cases where prisoners are escorted for treatment at the A&E departments."