Four people were arrested at the scene, a man and a woman from Jersey and a man and a woman from Liverpool.
The arrests follow an undercover operation involving Customs and States police officers and colleagues from the Dorset and Merseyside constabularies.
A force spokesman said that the surveillance team saw a package being handed over.
Heroin was later found in a car.
‘The four people have been detained in custody to be interviewed,’ she said.
‘Their names cannot be released until they have been charged.’
