Police are hunting a suspected gunman after he was spotted riding on a motorbike by a fellow motorist.
Between 5.50pm and 6pm on Sunday August 9 on the A472 Hafodyrynys Road, Crumlin, a driver was overtaken by a biker on a lightweight motorcycle.
The driver of the car reported that he saw the motorcyclist holding an object that he believed resembled a firearm.
The rider of the motorcycle was wearing navy blue jeans, a black leather jacket and a black helmet.
The road was temporarily closed from 6.15pm to 8.30pm between Lower Race and the Old Washery.
Police are keen to speak to anyone who was travelling along the A472 at the time and may have witnessed the incident.
Detective Inspector Huw Watkins said: “I would like to reassure members of the public that no-one was hurt as a result of this incident but we are continuing to undertake enquiries to clarify exactly what happened.
“There may be a perfectly innocent explanation for the incident so we would like for anyone with any information to speak to us.
“If you are the rider or you saw the incident please contact us to assist with enquiries.”
Anyone with information should contact Gwent Police on 101.