Carroll, who isfacing an eight-week lay-off due to a knee injury, was with his West Ham team-mates in Dublin for a weekend Christmas party after the Hammers beat Chelsea 3-1 on Saturday.
A spokesman for the Garda press office in Dublin said officers received a report of an incident at 2.30am on Monday.
A press photographer claimed he had been assaulted in the capital's main shopping district, Grafton Street.
Officers at the city's Pearse Street station are investigating the incident.
Source: Newcastle United Mad