A dozen employees and more than two dozen animals had to be evacuated from a Westbury animal hospital under a scorching summer sun Wednesday, following a chemical reaction between two cleaning chemicals, officials said.

Nassau County Fire Marshal Vincent McManus said the animals, dogs and cats were sheltered in private, air-conditioned vehicles; others were kept out of the blazing sun in the specially designed mobile firefighter rehab unit -- a vehicle usually used to aid firefighters working under harsh summer and winter elements.

Five employees were treated at the scene, McManus said.

The incident occurred around noon at the Veterinary Referral & Emergency Center of Westbury on Cantiague Rock Road, officials said.

McManus said the clinic was doing a routine cleaning when two chemicals reacted -- causing "a toxic cloud."

Temperatures outside hovered around 90 degrees at the time, according to the National Weather Service.

None of the animals were injured, McManus said, adding that the motor home-sized rehab unit helped animals and staff weather the weather.

advertisement | advertise on newsday

He said hazmat personnel were able to vent the building, clean the chemicals and that staff and animals re-entered the site sometime around 1:15 p.m.