Thousands of German football fans brought parts of central London to a standstill ahead of their team's Europa League match against Arsenal.
Some 20,000 FC Cologne supporters have come to London, and briefly brought the West End to a halt as they marched down Oxford Street.
It is the first time in 25 years Cologne has played in an international club competition.
Police said flares were let off but reported no 'significant disorder'.
The game was due to start at 20:05 BST but Arsenal say kick-off has been delayed by about an hour in the "interests of crowd safety".
The Bundesliga estimated around 20,000 fans had travelled to the capital to support their team.
It added only 2,900 tickets had been allocated to the away fans for tonight's match at the Emirates stadium in north London.
In a statement the Met Police said: "At around 15:00 BST on Thursday, 14 September a large group of football fans gathered in Oxford Street.
"The group was at the location for about 30 minutes whilst they boarded public transport to travel to a football match this evening.
"They did throw bottles and let off flares, but there was no significant disorder, police were on scene and there have been no arrests. The group has now left the area."
Source: BBC NEWS