An officer was assaulted after police were called to a gathering of 40 people in The Meadows in Stamford.
Lincolnshire Police said the group were dispersed and two arrests were made - both have since been released. They will be required to attend a voluntary interview.
A man was also assaulted and received minor injuries.
Grantham Inspector Gary Stewart condemned the behaviour as ''totally unacceptable.''
''This behaviour is totally unacceptable and will not be tolerated. We are looking into this further and those involved will be dealt with.''
“A Dispersal Order will be in place across Stamford again on the weekend to ensure those who are out and acting responsibly can do so without having their day ruined by the minority.”
It comes as the force said Chief Inspector Andy Morrice said there was a 20% rise in calls.
They attended a number of locations in Skegness following reports of groups of more than six young people gathering and drinking alcohol.
Coastal Inspector Colin Haigh called on parents to know where their children are.
:“These youngsters are the responsibility of their parents and parents should ensure they know where their children are. We will not tolerate this behaviour and we take these incidents very seriously and will take further action. Those breaking the rules are not only putting themselves at risk but others also.''
Last weekend was the first weekend since bars and pubs could open to customers sitting outdoors under the new rules.