A search is under way after a car went into the River Lee.
Emergency services could not confirm if anyone was in the vehicle after gardai alerted the Coast Guard to the incident in Cork city shortly after 6am on Friday.
It is understood a member of the public saw the car in the river with the bonnet submerged and the boot sticking out.
A Coast Guard helicopter was sent to the scene along with a search and rescue team from the RNLI unit based in Crosshaven.
A Garda spokesman said the incident happened near the Lee Rowing Club.
The river would have been about 16ft (5m) deep at the time in the area where the vehicle was last seen but the flow is expected to increase over the next few hours as the tide goes out.
The RNLI lifeboat crew was anchored at the spot where the car was last seen and a dive team was due on site.