Yesterday it was confirmed that police had discovered a large-scale cannabis farm on Kent Street, in Coalpool, over the weekend.
The find was shared by West Midlands Police Cannabis Disposal Team on social media, with 711 plants discovered inside what was once Abu Bakr Boys' School. The plants have a street value of £700,000.
Then on Monday night at around 6pm, residents saw three men pulled from the roof of the building. The men have been detained by police.
This was later confirmed by West Midlands Police drone team, who assisted Walsall Police at the scene.
A resident said: "It has been crazy, we didn't have a clue what the police were doing around here.
"Then we found out through the news that it was a cannabis farm, but the police were still here in the evening.
"So we were keeping an eye out the window, then around 6pm they started surrounding the building.
"They got three people out of the upstairs, I have no idea how they got up there or how long they have been there."
The school closed down over the lockdown period, and has been boarded up for quite some time.
One resident said police they had seen police in the area for around a week, with more officers around on Friday and throughout the weekend.
Another said they had seen armed police show up on Sunday at around 4am.
Whether the people detained from the loft of the building are connected with the farm is currently unknown.
One resident, who lives near the building and asked to not be named, said: "It's usually quiet around here so you notice when there's a lot of cars around.
"The building used to be a school, but it closed around Covid time.
"They've been around for around a week, and there was a lot of them on the weekend, but nothing is happening.
"Nobody has knocked our door to say anything or tell us to keep our eyes peeled for anything.
On Monday afternoon, a sole police car was parked on the premises of the old school, with officers sitting inside.
West Midlands Police has been contacted for comment.