Cocaine with a street value of £8.25m has been found by the UK Border Agency in a container in Essex.
The discovery at Tilbury is the biggest single detection of class A drugs at the port in six years, the agency said.
The drugs were inside an industrial digger machinery, shipped by container from Surinam, South America, and destined for Holland.
Sections of the machinery had been hollowed out and filled with 145 packages of cocaine, totalling 166kg.
Marc Owen, from the UK Border Agency, said: “The actions of our officers at Tilbury have prevented a massive quantity of cocaine from flooding the European market.”