A 16-year-old from Chorley was arrested on suspicion of possession and intent to supply a Class B drug.
He was stopped by officers in the town centre around 4pm yesterday.
They seized £150 in cash and nine bags of what is believed to be cannabis following a search.
Officers also found drugs, a zombie knife, and a BB gun during a search of the suspect’s home address.
The teenager has been released whilst investigations continue.
Chief Inspector Chris Abbott said: “Anti-social behaviour can take many forms.
“They are a blight on our communities, and we will not tolerate it in Chorley.”
The officers who arrested the 16-year-old were out on additional patrols as part of Operation Centurion.
Operation Centurion is a county-wide crackdown on anti-social behaviour, led by Lancashire Constabulary and backed by Police and Crime Commissioner Andrew Snowden.
Mr Snowden said: “I’m absolutely committed to cracking down on anti-social behaviour and I will continue to work closely with the Chief Constable to ensure the Constabulary has the resources needed to get tough on ASB and keep our communities safe.”