An oxygen tank exploded at the University Medical Center of Princeton in Plainsboro on Thursday night injuring at least two people.

Fire and rescue at University Medical Center of Princeton in Plainsboro (@GloriaHansen via Twitter)

In a statement the hospital says the explosion in a patient room at 8:50 p.m. Thursday night left one staff member seriously injured and taken to a burn center.  The injured visitor was treated and released.

As a precaution, the hospital says they moved 18 patients to other locations within the hospital. Operations returned to normal on Friday and couselors were on hand to provide emotional support for patients, staff and family.

The Middlesex Police Fire and EMS Facebook page say the explosion happened on the third floor of the hospital located on the northbound side of Route 1.

The cause of the explosion is under investigation but the hospital says it is likely the result of an accidental oxygen tank explosion.

Witnesses tell the Times of Trenton a woman was taken away with what looked like a serious facial wound. Planet Princeton tweets that patients and staff heard a "boom" and that the explosion caused a one-alarm fire that was brought under control.

Plainsboro Fire Department spokesman Lt. Tom Healey told that ceiling tiles in the affected room had buckled from the explosion and there was a "haze" when first responders arrived. A witness told the website that the room was "demolished."

Tweets from the scene indicate several windows were blown out.

The hospital was located in Princeton until 2012 when the new 400-bed facility was opened on Route 1.