Beach clashes between police and visitors refusing to respect COVID-19 restrictions in Belgium have led to two resorts saying day-trippers were not welcome.

Knokke-Heist and Blankenberge, two popular towns on the Flemish northern coast near the border with the Netherlands, said they took the step to "guarantee public security."

Police arrested several people on Blankenberge beach, on Saturday, after a brawl broke out involving youths they had told to leave for refusing to follow virus safety measures.

The two towns and the coast have been swamped by visitors heading to the coast during the hot weather, while at the same time the country tackles one of the most serious coronavirus outbreaks in Europe.

The troublemakers were barred from the resort which was also closed to day trippers, Blankenberge mayor Daphne Dumery said.

"We need a quiet period... anyone who comes to Blankenberge must have a good reason to be here. With this step, we are trying to restore calm," she added.

The nearby upmarket resort of Knokke-Heist took a similar step after "dozens of incidents, during the day and the night," a city council statement said.

The council "felt obliged to take drastic measures. To ensure public security, day visitors will no longer be allowed."

Road checks are in place where people will have to show proof that they either live in the town, are staying in a hotel or rented apartment, or work there, the statement said.

"All vehicles will be checked. Anyone who does not have a valid reason to be in Knokke will have to turn around and leave immediately," it stated.

The SNCB train operator told passengers to check whether they would be allowed to visit the two towns before setting out.

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