A Dublin nightclub was forced to evacuate 800 people after a canister of gas was released on the dancefloor.
Staff at Bad Bob's, which is located on Essex Street in Templebar, were alerted at 1.45 a.m. today.
The Gardai and the fire services were called and the bar was evacuated. Three customers, one of them an asthmatic, were taken to St James's Hospital with breathing difficulties and sore eyes.
They were treated and discharged shortly afterwards. Gardai are carrying out an investigation into the incident. "We haven't yet established what it (the gas) was and nothing has been found.
We will be talking to the people who were admitted to hospital," said a Garda spokesman. Members of the Garda technical bureau are to investigate the scene at the club.
Ms Gloria Gallagher, the general manager of Bob's, said she believed the gas had been pepper spray. "There were no chemical attacks, it was just some fellow who let off pepper spray," she said. "It spoiled a few people's nights but I think they'd had enough at that stage."
It was the first such incident at Bob's, which has since re-opened for business. But Ms Gallagher said Gardai had told staff that pepper spray was becoming an increasing problem in Dublin pubs and nightclubs. Pepper spray is an inflammatory agent that can affect a person's eyes, nose, throat and lungs. It causes temporary blindness, reduces breathing and can create an intense burning sensation on the surface of the skin. The chemical substance is illegal in this country, although it has been acquired by Garda for use as a 'less than lethal weapon' in emergencies.