The incidents, between 30 January and 4 February, include reports of assaults, demonstrators being forced to leave by masked men, and a Dambusters flag being burnt, according to the Lincolnshire force.

The incidents have been reported in areas where multiple protest camps have been set up at different entrances around the perimeter of the RAF Scampton site.

The government plans to house up to 2,000 asylum seekers at the site near Lincoln - a move that has been met with opposition from locals, politicians and historians.

Officers said a Dambusters flag was set alight between noon and 1pm last Tuesday.

Authorities also said they received a report that a group of people wearing face masks arrived at the protest camps and forced those there to leave without their belongings in the early hours of last Saturday.

And the force said there were multiple reports of assaults on Sunday.

Lincolnshire Police said: "Incidents reported to us which have required a larger policing presence are suspected to have involved a minority of protesters, many of whom are believed to be from outside of the county."

Officers have appealed to anyone driving on any of the nearby roads or those who captured any footage of the reported incidents to get in touch.

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The airfield, which closed in 2022, is the former home of the Red Arrows aerobatics display team and the Dambusters - the squadron that carried out one of the Second World War's most famous air raids.

The officers' mess was given listed building status by Historic England in October recognising the structure's architectural and historical importance.

It means there are tighter controls over what changes can be made to it, while the Home Office stressed that "heritage assets" at the former base site would be safeguarded.

Lincolnshire Police said it would continue to patrol the area.