PARIS -- The spokesperson for the Paris prosecutor's office says a man on a list of national security threats has been detained near a French military air base in the northern region of Normandy.

Spokeswoman Agnes Thibault-Lecuivre said the arrest occurred Friday in Evreux, 97 kilometers (60 miles) west of Paris. She said authorities found a pump-action shotgun and two revolvers in the bushes near his car.

She said the unnamed man also claimed that a USB key discovered in his car contained a pledge of allegiance to the Islamic State of Iraq and Syria (ISIS).

Thibault-Lecuivre said experts have not yet had time to verify this claim. She said authorities have not linked this arrest with Sunday's presidential election, which is taking place under heightened security.