Police in India have arrested three people including a doctor after a man was killed in a rare accident involving a Magnetic Resonance Imaging (MRI) machine.

32-year-old Rajesh Maru accompanied a female relative to BYL Nair Municipal Hospital in Mumbai over the weekend, where she was to have an MRI scan.  He was holding an oxygen cylinder for the patient, and hospital personnel reportedly failed to tell him to leave the metal object outside of the MRI chamber - but they did ask him for help getting the woman onto the machine's scanning platform.

"The ward boy asked him to help.  They said it was okay.  He went close to the machine and instead got pulled along with the oxygen cylinder inside the machine.  Instead of taking responsibility, the hospital workers scolded us for Rajesh having gone close to the MRI machine with the cylinder in his hand," said Maru's sister Priyanka Solanki, who was also present in the MRI room.

The arm holding the cannister was jammed into the powerful magnetic device and reportedly mutilated.  But Mr. Maru was killed when the cannister ruptured and he inhaled the pure oxygen gas into his lungs, causing "pneumothorax" - a condition where excessive air enters the lung pockets.

"Excessive quantity of oxygen entered his body from the cylinder, which is also harmful," said a medical examiner.  "He seemed to have died instantly because of that.  Apart from that there were injury marks on both his hands."

Police are investigating the incident as criminal negligence.