A mainland court has sentenced four people described as key figures in cross-boundary fraud cases to life in prison.

The Supreme People's Court said the four defendants all left China to form telecom fraud organisations, with one of them, surnamed Yu, organising a number of people to go abroad to commit crimes.

The announcement comes as the court released sentences over seven telecom-related fraud cases in the country.

Last month, a mainland actor was rescued from a telecom syndicate in Myanmar.