CLASS A drugs, weapons and cash were found by police following an operation in the grounds of a Clacton church.
Tendring Police said the sting in the grounds of the Our Lady of Light and St Osyth Church, in Church Road, was part of its Operation Raptor initiative.
Chief Insp Russ Cole, district commander, described it as "a significant breakthrough" in tackling drug dealing in the Clacton area.
He said: "At this time of year we typically have drug dealers coming from London to exploit our town early before the summer season.
"We have put some extra resources in place for our Operation Raptor team alongside our community policing team.
"Thanks to a proactive intelligence-led operation around the grounds of the church, we stopped and searched a woman.
"Subsequent enquiries led to a property nearby where drugs, knives and £3,000 in cash was found and seized.
"There was a significant quantity of wraps, including heroin and crack cocaine.
"It is a significant bust and follows through on our promise to take drugs off the streets - and that commitment will continue throughout the summer.
"My message to anyone coming to Clacton to supply drugs is that we will be out and about and you will be caught."
An 18-year-old woman, from London, was charged with possession of Class A drugs with intent to supply in relation to the incident.
She was due to appear at Chelmsford Magistrates' Court today.