CCTV images have been released after a projectile was thrown during a football match, hitting a seven-year-old boy.
The nitrous oxide canister was thrown from the away end at Southampton's match against Liverpool at St Mary's on Saturday, police said.
A young Southampton fan, who was in the Northam Stand home section, sustained minor injuries when he was struck.
Hampshire police said it wanted to speak with the man pictured in connection with the incident.
Liverpool won the match 2-1.