Armed police sealed off part of Huddersfield in a late-night manhunt.
It is thought they were looking for a suspect.
Bewildered residents reported seeing police “charging” up an alley by a house, “shouting armed police”, a man being led away in handcuffs and two police cars being moved to block the road at different points.
One, Ash Gavin, said: “We watched the whole thing.
“Ten police vehicles including a riot van, video van, dog vehicle and normal police vehicles parked up and 15 armed police men in body armour carrying guns along with some police dogs got out.
“About six of them charged down a back alley under a house shouting ‘Armed police’ whilst about another six were waiting on the street.
“The guys came back up with one man in handcuffs and put him in a van. At about 11.45 they started letting vehicles through again.
“About half the vehicles left at midnight and the other half were parked up till 1am just sat at the roadside with their lights off.
“I think they definitely have an obligation to inform residents what’s going on but I doubt they will.
”A woman said she saw police in the garden of her neighbour, who she believed was out at work at the time.
She alleged they broke in but thought they may have been looking for someone else as “the man who lives there is a really nice and quiet bloke.”
Commenting, she said: “After about 10 minutes police burst through his door.
“They brought him home from his work at about 2.30am.”She did not believe that he had then been arrested.
Another neighbour, Chris Thompson, spoke of his shock at witnessing the event.
“I was expecting a pizza delivery so opened the door to have a look outside”, he said.“I saw a policeman and he told me to go back inside.
“It was quite confusing.”A West Yorkshire Police spokesman confirmed the investigation, which formed part of ongoing enquiries, but said they could not expand on it.
In unrelated investigations, police would like to speak to the people pictured in the image gallery below. The people pictured in the images may be witnesses as well as suspects. If you recognise anyone, contact police on 101 quoting the reference number on the image caption.