Lincolnshire Police have arrested a Lincoln man on suspicion of a robbery at a city off licence and another attempted robbery.
Officers arrested a 39-year-old local man on suspicion of the robbery at The Grapevine off-licence in Burton Road on February 10.
A member of staff was threatened with a weapon and cash was stolen during that incident
He was also arrested on suspicion of the attempted robbery at Select and Save in Baggholme Road, on February 9.
He has been released on police bail pending further enquiries until April 4.
As previously reported, the robbery at The Grapevine and the attempted robbery at Select and Save were part of a string of four possibly related robberies police are investigating.
Charity Crimestoppers is also offering a reward of up to £3,000 for information on the incidents.