Police are investigating after an armored truck driver fired his weapon during an attempted robbery in Miami Wednesday.

The incident happened outside the El Brillante supermarket in the area of Southwest 17th Avenue and 11th Street around 1 p.m., Miami Police said.

According to police, the Dunbar Armored driver was wheeling a cart into the supermarket when he was attacked by a suspect.

Surveillance footage showed the suspect knocking the guard to the ground and running away as the guard pulled out his handgun and opened fire.

The driver fired four shots but it's unknown if he struck anyone, police said.

The suspect fled the scene but it was unknown if he took anything. Police said a person of interest was in custody but it's unknown if that person is the suspect.

"We are not exactly sure if he struck the offender, because we don't have him on scene," Miami Police spokesman Freddie Cruz said. "Again, we have a person of interest but we're not exactly sure if that's the offender at this moment."

No other information was immediately known.

Check back with NBC 6 for updates.