Five people have been arrested in Merseyside as part of an operation to stop cocaine with an estimated street value of £166m reaching the UK.
The investigation began last year
The arrests were made during raids on seven addresses in Merseyside, Lancashire and North Wales on Tuesday.
The 1.66 tonne cocaine haul was found in sardine tins in Holland, Merseyside police said.
Two men were arrested on drugs charges and two men and a woman were held on suspicion of firearms offences.
Police said two men, aged 33 and 34, from Garston, Liverpool and Preston, Lancashire, were arrested on suspicion of conspiracy to supply Class A drugs.
Two men both aged 35, and a woman, aged 23, from Garston, were arrested on suspicion of firearms offences at a separate address.
The haul is equal to 10% of the total amount of class A drugs seized in the UK in 2003
The investigation involved HM Customs, Merseyside Police and Dutch and Spanish authorities
Detectives recovered 3,000 rounds of ammunition and two silencers.
The arrests follow an investigation by British, Dutch and Spanish authorities.
Det Ch Insp Mark Wadmore, of Merseyside Police, said: "The arrests today are the culmination of an extensive investigation into the supply of Class A drugs on Merseyside."
The investigation, involving HM Customs, Merseyside Police and Dutch and Spanish authorities, began in September.
A Merseyside Police spokeswoman said the drugs were seized in a warehouse in Holland but were due to be brought into the port of Liverpool.
The haul is equal to 10% of the total amount of class A drugs seized in the UK in 2003, according to Home Office figures.
A spokesman from the Independent Drug Monitoring Unit said the street value of the drug would depend on the purity of the cocaine.
Merseyside Police said the drug was 92% pure and therefore had a high street value of £166m.