This is the shocking moment two rival gangs sparked chaos when they started fighting in a hospital.
Staff at the King Mongkut Memorial Hospital in Phetchaburi, Thailand called police to intervene when the men started throwing punches on September 9.
Hospital CCTV footage shows the three men from one of the groups shouting, which provoked those from the other group.
Officers arrived at the scene and immediately separated two youngsters while they trying to throw punches at each other.
However, they were unable to control them and the brawl escalated with around 20 people grappling with each other and the police.
Doctor Aekchot Peerathammanon said the fight started when members of the different gang were being treated at the same hospital following a bust-up earlier in the evening.
He said: "They didn't expect to see each other in the same hospital after fighting somewhere else.
When they saw each other the fight erupted.'' The group damaged hospital equipment and sent terrified nurses and patients running for safety.
The men were also bloodied from their wounds when the police came to stop them.
Police Lieutenant Supanit Meephan said the hospital staff asked them to stay and guard the area because the two groups might start fighting again.
Several suspects were arrested at the scene and police are now searching for other alleged offenders.
He said: "Some of them had to be admitted to hospital because of their injuries so we will stay here to keep the area safe.
The hospital administrators are afraid that friends of the patients will riot again if we leave."