Preston police arrested two people and recovered nearly £400k of cannabis plants after three raids on houses in the city today.
Three people are now in custody after the daylight operation.
A spokesman for Preston police said: "Today officers from the Preston Neighbourhood Policing team executed 3 simultaneous warrants at 3 addresses on Osbourne Street, Broadgate.
"During the warrants all 3 properties were forced open by officers.
"This resulted in an estimated total of £385,000 worth of cannabis seized.
"Two people have been arrested for drugs cultivation and immigration offences and have the pleasure of staying in our custody suite tonight.
"We will continue to disrupt criminality and make sure that these drugs do not reach our streets. Just remember no matter what kind of door you have, our big red key fits any key hole."