Unrest at Celtic v Rangers U17s Glasgow Cup Final
Smoke bombs were let off and seats ripped up by rival fans during Monday night's Glasgow Cup Final between Celtic and Rangers under-17 teams.
The match, at Partick Thistle's Firhill Stadium, was delayed for safety reasons to allow smoke to clear from the pitch.
Police Scotland made three arrests at the game, which Rangers won 3-2.
A 19-year-old man was arrested outside the stadium over an alleged assault. Two 17-year-old men were arrested inside over alleged pitch incursions.
The game was attended by about 6,000 supporters.
Both clubs said they are helping police with their investigations.
A Celtic spokesman said: "We are looking into last night's match in more detail, together with all the relevant authorities, and clearly will deal with any issues appropriately."
A spokesman for Rangers added: "It is disappointing that the off-field incidents at the Glasgow Cup Final last night detracted from a good game of football.
"The club will assist the police with all their inquiries."