Police clamped down on illegal raves taking place over the Easter bank holiday weekend.
Essex Police said around 100 people attended an unlicensed music event on land off Buckingham Hill Road in the town of Stanford-le-Hope on Saturday night.
The force seized music equipment from the event and is now working to identify those who fled the area as officers arrived in order to issue fines for a breach of Covid-19 regulations.
Elsewhere, Kent Police thwarted an illegal rave that was planned to take place at Polhill in Sevenoaks on Saturday.
The force said it received information that an event was being planned that evening and officers encountered large groups of people in the area.
Police stopped the event from being set up and seized music equipment, before moving people on from the site.
Superintendent Simon Thompson, from Kent Police, said: “We appreciate that lockdown has been tough for everyone and over the long bank holiday weekend people may be tempted to attend these events but I must be clear that Kent is not open for unlicensed music events.
“As our officers have shown, we will move people on who come to Kent for this reason, seek to prosecute the organisers and seize equipment that they may bring with them.
“We want people to have fun and enjoy themselves but not at the expense of others in the community.”