Scottish football: Celtic fined over fans behaviour
It is the fifth time in three years Celtic have been charged by Uefa over supporter behaviour.
Fans clashed with police after fireworks were set off in the Celtic end of Stadion Maksimir as the Scottish champions lost 4-3 in Croatia.
Despite that December defeat, Celtic qualified for the last 32.
The fine - imposed by Uefa's control, ethics and disciplinary body - was announced as Celtic and their fans travelled to Italy for the Thursday's second leg against Inter Milan.
Reacting to the news, Celtic assistant manager John Collins stressed that it is "vitally important" that travelling supporters match what he suggested was the good behaviour displayed by home fans during the 3-3 first-leg draw in Glasgow.
"We are obviously disappointed," he said. "We had 60,000 last week and it was unbelievable behaviour from every one of them, the atmosphere, and that is what Celtic is all about.
"One or two are causing problems and hopefully that is the last we hear of it.
"They are representing a wonderful football club and throughout the years the vast majority of them have been impeccably behaved and we have a great reputation throughout Europe.
"One or two we have to try to weed out."
It's not the first time the Celtic fans have been in trouble though - there is quite a history in recent years:
Bhoys behaving badly - Celtic's UEFA fines
2011 - fined £12,600 in 2011 after supporters made pro-IRA chants during Europa League home match against Rennes
2012 - fined a further £21,000 after fans unfurl a banner criticising Uefa and set off flares away to Italian side Udinese
2013 - fined £4,200 when a firework was let off during the Champions League qualifier against Cliftonville at Celtic Park
2014 - fined £42,000 for "illicit" banners at home defeat by AC Milan
2015 - fined £7,300 for crowd disturbance away to Dinamo Zagreb