Class A drugs with a potential street value of £27m have been found hidden inside a lorry carrying vegetables at a port in the east of England.

About 400kg of cocaine and heroin were discovered hidden among a load of onions and tomatoes at Killingholme port in north Lincolnshire in an operation led by the National Crime Agency.

The unaccompanied lorry arrived from the Hook of Holland on Wednesday containing the drugs, according to the NCA, who were assisted in the seizure by Border Force and Humberside police.

A 45-year-old Romanian national was arrested on suspicion of conspiring to import class A drugs on the day of the raid after he tried to drive the lorry away. He has since been released under investigation.

NCA branch commander Jayne Lloyd said: “The seizure of this significant amount of controlled drugs supports our mission to protect the public from harm. We will continue to work with law enforcement partners to detect and disrupt criminal activity.”

Liz Versi, the director at Border Force North, said: “This was a substantial seizure and demonstrates the vital work Border Force officers are doing to take class A drugs out of circulation. Working with law enforcement partners, like the NCA, we are determined to prevent drugs from being brought into the country and causing harm to our communities.”