Seven people have been arrested during raids at 15 addresses in Kirkby, St Helens, Knowsley village and Fazakerley.
The operation, codenamed Operation Decade, is targeting those believed to be involved in gun and drug crime.
The raids are the culmination of a 12-month investigation.
Six men and one woman, have all been arrested on suspicion of conspiracy to supply Class A drugs.
A further two men have been arrested and a substantial amount of cash has been recovered from a property in St Helens as part of the operation
The operation carried out today reinforces the Force's commitment to tackling the scourge of drugs and guns in our communities.