A police officer was attacked while helping to break up a house party which attracted "up to 100 people", it has emerged.
Officers were called to the party in Solihull's Old Lode Lane in the early hours of Saturday morning.
The police officer was kicked but was not seriously injured during the incident, the force said.
A police spokeswoman said a tip-off from the public led to a knife being found beneath a car in a nearby road.
No arrests were made and it is understood those at the party were in the process of leaving when police arrived.
From Monday people will be allowed to meet outside - including in private gardens - in groups of up to six, or as two households.
Police called to a mass gathering in Solihull, on arrival an officer was assaulted. A member of the public reported suspicious behaviour from offenders as they made off. PD Jet conducted a search & located a large knife hidden under a car 🔪 🚗 pic.twitter.com/BnPVfZRYTj— WMP Dog Section (@WMPDogs) March 27, 2021