According to police, on Wednesday around 5:20 a.m., a man entered a Subway on Route 75 and demanded money while displaying a handgun.
The man then fled the store and allegedly tried to rob a person sitting in a car in the parking lot.
Police say the store clerk then realized the suspect was using a fake gun, tackled him to the ground, and held the suspect there until police could arrive.
Authorities arrested 18-year-old Bryan Minor-Doherty of Windsor Locks.
He has been charged with Criminal Attempt to Commit Robbery in the 2nd Degree, two counts of Threatening, and two counts of Breach of Peace.
Minor-Doherty was held on a $25,000 bond and appeared in court on Wednesday.