Police were called to a funeral after about 60 people attended, ignoring coronavirus lockdown measures.
Dozens of mourners attended the service at Streetly Crematorium, in the West Midlands, on Saturday, the Local Democracy Reporting Service said.
West Midlands Police said people were encouraged to disperse but failed to do so and no further action was taken.
Walsall Council said main gates at the site would now remain locked, with only controlled access granted to mourners.
The authority limits mourners at a funeral to 10 people, in line with government guidance.
Ch Supt Andy Parsons, of West Midlands Police, said: "Unfortunately we were unable to encourage the mourners to adhere to current restrictions and the funeral continued in breach of the new government guidelines issued last week.
"We understand that this is deeply distressing time for bereaved families and friends but there are restrictions on the number of people permitted to attend funerals to protect everyone from the spread of Covid-19.
"We will only enforce the law as an absolute last resort, but we must stress that these restrictions are in place to prevent more deaths from this pandemic."
The council's portfolio holder for community, leisure and culture, Garry Perry, said staff would man the crematorium gates from this week.
"Of course we recognise the distress caused at present by the restrictions in place," he said. "However, the guidance is clear - the definitive way to beat the virus is to reduce social contact, stay at home and save lives."