What started as a joke, soon escalated to full blown confrontation as Police in Belgium had to use tear gas and water cannon to break up a crowd of about 2000 young people who had gathered for a fake concert that was announced on social media as an April Fools’ Day joke.

The event in Brussels’ Bois de la Cambre park was held in defiance of the country’s Covid-19 saftey measures.

Four people were arrested while three police officers were injured in clashes, according to reports.

The announcement for the concert which boasted of featuring famous DJs was posted on Facebook in March.

Despite organisers saying the invitation was a hoax, many people still turned up.

“We are all depressed. I’ll be 18 in two weeks, we want to take advantage of our youth,” one student who attended the gathering told journalists.

“We came not to annoy the police, but to show that we also have a life and want to enjoy it.”

Under coronavirus restrictions in Belgium, outdoor gatherings are limited to four people.

Prosecutors say they have started an investigation to find out who was behind the Facebook post.

Brussels Mayor Philippe Close said he could understand people wanting to go outside in the spring weather, but such gatherings would not be tolerated.

Belgium, with a population of 11.5 million, has recorded more than 882,000 coronavirus cases and 23,000 deaths.

It is one of a number of European countries to increase restrictions amid a rise in cases.