Dutch carrier KLM says a "disturbed passenger" injured himself and a co-pilot on a flight to China before being overpowered by crew and other passengers.

KLM issued a brief statement Tuesday saying the incident happened Sunday on flight KL897 from Amsterdam to Beijing. The carrier says the flight was never at risk and landed as planned in Beijing.

KLM says the co-pilot was treated for a minor injury in Beijing and has since returned to the Netherlands. The passenger injured himself in a toilet.

A KLM spokesman declined to give more details.