PARAMUS - (AP) - Two of the three workers injured when an MRI machine exploded at a New Jersey animal hospital last week have been released from the hospital.

But the third person hurt in Friday's accident at the Oradell Animal Hospital in Paramus remains hospitalized in critical but stable condition.

Authorities are still trying to determine what caused the explosion. They said 60 animals and 100 employees were in the building when the blast occurred.

Authorities released the three victims' names on Monday. They said 49-year-old Joseph Bijas, of Hillsboro, and 53-year-old John Fitzpatrick, of Freehold, have both been released from the hospital.

The most seriously injured worker - 37-year-old Jeremy Hogan, of Ridgefield, Connecticut - remains hospitalized but is expected to recover.

The Occupational Safety and Health Administration is investigating the accident.