The police were called to a petrol station on Carr Road, Peterborough, on August 8 at 2:20pm to reports of a robbery.
The suspect, a man, entered the premises and cigarettes, tobacco and cash was stolen.
A spokesperson for Cambridgeshire Constabulary said: "A man in his 30s was subsequently arrested in Padholme Road at about 3pm on suspicion of robbery and possession of Class C drugs.
"Whilst in custody, he was additionally arrested on suspicion of further drug offences, assaulting an emergency worker, fraud by false representation and theft from a shop.
"He remains in custody at Thorpe Wood Police Station at this time."
The investigation is ongoing, and the police have confirmed that no one was injured during the incident.