A security guard was injured while detaining a man in Market Place, Mansfield, following the robbery at Betfred at about 11.15am today.
He was taken to hospital but his injuries are not believed to be serious.
Officers arrested a 44-year-old man on suspicion of robbery and wounding with intent in connection with the incident.
Fire crews deployed to ‘large’ blaze in Mansfield – with people evacuated as flames spread to nearby properties
Letter: Unfair that disabled can no longer access water park
Creswell properties evacuated as fire crews tackle field blaze
Large fire in Kirkby may have been a 'deliberate or a careless act'
New council boss reveals ambitious plans for Mansfield
Shortly before 3pm, staff at the bookmakers were closing the store early. No members of staff made a comment in relation to the robbery.
A sign on the door simply said: “Due to unforeseen circumstances we are closed until further notice. Sorry.”
One trader at the scene said: “It is a surprise. We didn’t see anything really, just a lot of police activity around the corner.
“It is a shock that this happened.”