In a “tragic” trial, residents in Lufeng in southern Guangdong province were invited to see the trial via an official notice on social media to see the sentencing of seven people accused of drug-related crimes and others found guilty of murder and robbery.

After the sentencing - which took place in a huge stadium - eight of the accused were taken away and immediately executed.

William Nee at Amnesty International said it was “absolutely tragic”.

Speaking to MailOnline, Mr Nee said: "The mass sentencing rally that took place — including the execution of eight people involved in drug-related crimes — is absolutely tragic and barbaric.

"Despite China continuously executing hundreds if not thousands of people per year for drug-related offences, China is actually experiencing a growth in drug manufacturing and trafficking — which obviously shows the limitations of the 'kill the monkey to scare the chickens approach.'

"China should immediately end the use of the death penalty for offences that do not meet the threshold of 'intentional killing' in international law, and devise other ways to tackle the drug problem that does not perpetuate a cycle of violence."

The accused were brought to the stadium on the back of trucks and were each flanked by four officers wearing sunglasses.

They were brought to a small platform usually used as a running track one by one to have their sentences read, according to the video of the trial.

Thousands watched the show trial and some reports say students in school uniforms attended, witnesses claimed.

Some stood on seats while others crowded onto the centre of the field.

Others filmed with their mobile phones while others chatted and smoked.

China executes more people every year than the rest of the world combined.

The official figures are undisclosed and considered a state secret.

Last year it carried out about 2,000 death sentences, according to estimates by Dui Hua Foundation, a human rights NGO based in the United States.

Public trials in China are rate, but the country’s justice system favours prosecutors as Chinese courts have a 99.9% conviction rate.

The open trial and sentencing are not new for Lufeng.

Eight people were sentenced to death for drug crimes and summarily executed five months ago in a similar show trial, according to state media.

The show trials are reminiscent of the People’s Republic when capitalists and landowners were publicly denounced.

They have made a come back in recent years in some areas, most notably for cases of alleged terrorism in the far west region of Xinjiang.