JACKSONVILLE, Fla. -

An 18-year-old was sentenced this week to 40 years in prison for seven armed robberies and one unarmed robbery case.

Matthew Johnson pleaded guilty to the crimes in August.

The teen used a handgun and a BB gun to hold up seven victims between January and February. Johnson took the victims' wallets and other personal items during the crimes.

Johnson also snatched a 13-year-old's backpack during the crime spree. He was unarmed in that incident.