Armed police carried out a raid on a terraced house in Freckleton after a tip-off.
Later it was revealed a blank-firing gun was seized from the premises along with ammunition. No-one was arrested, although a man, aged 47, is due to be interviewed at a later date.
A Lancashire Police spokesperson said officers had carried out “a pre-planned warrant” at an address on Kirkham Road in Freckleton at about 4.30pm on Wednesday.
“A blank-firing pistol was recovered along with a quantity of ammunition,” said the spokesperson.
“A 47-year-old man from Freckleton will be spoken to at a date to be arranged.”
An eye-witness said: “It was quite dramatic. The police were heavily-armed and blocked off the road before entering the house.”