Armed police have carried out a second operation in the area around Montagu Street in Kettering.
A number of readers phoned the Northamptonshire Telegraph to say they had seen a high level of police activity in the area on Thursday, April 24.
Armed police entered a property in Montagu Street and were supported by police dogs, as well as the force helicopter.
A crowd of about 60 people gathered near the scene near the junction with Tresham Street to watch the operation, with more waiting at the opposite end of the cordon.
Montagu Street was closed at its junction with Eskdaill Street and at the junction with Bath Road. Those cordons were lifted at 3.30pm, having been in place for about two hours.
Traffic travelling along Eskdaill Street was diverted down Victoria Street, while traffic heading west along Montagu Street was directed along Bath Road.
A spokesman for Northamptonshire Police said: “The raid came after a call from a member of the public.
“We have made a number of arrests and those people arrested are currently being questioned in custody.”
Speaking at about 3.30pm, a police spokesman added that the incident was now being scaled down, although some officers would be remaining at the scene.
An eyewitness to the raids said she was on the scene for more than an hour and a half.
The woman, who works nearby but who declined to give her name, said she had seen one person being led away by police.
During previous raids earlier this month, eyewitnesses took pictures of police marksmen and of suspects lying on the ground in Montagu Street.
Those raids, on April 3, saw drugs seized and several people arrested.
They took place in Montagu Street and Dahlia Road, Kettering, and in Minerva Way, Wellingborough.