A Swiss International Airlines plane from Zurich to Beijing was forced to turn back Sunday after two Chinese passengers fought above Moscow, a company spokesperson said Monday.

Myriam Ziesack told Xinhua over phone that the fight between the two Chinese passengers took place when the flight LX196, a direct flight from Zurich to Beijing, flew above the east of Moscow, more than six hours after its take-off.

Ziesack said the crew have succeeded in separating the two, but the captain decided to turn back, due to concerns that the fight could start again or be escalated.

Neither the crew nor the other passengers have been injured during the incident, she said.

When asked whether the company is considering to sue the two passengers, Ziesack said that "possible next step is still in discussion".

The two passengers were arrested by the police of the canton of Zurich and are currently under investigation. Zurich Cantonal Police spokesperson Werner Schaub said alcohol clearly played a role.