Preparations of the Euro 2008 are well on track six months ahead of the tournament, but the current plans for fan zones in small cities could be insufficient to cope with a potential avalanche of German fans. "We cannot compare Switzerland and Austria with Germany, or especially with Berlin, where we had one million supporters in the fan zone. I think the fan zones in Switzerland and Austria are in a size which is the needed size for this, it goes up to - in Vienna it goes up to seventy thousand and the others are around 20 to 40 thousand. So I think in the normal matches that will be sufficient," Martin Kallen the Chief Operating Officer for Euro 2008 said in a news briefing, one day ahead of the final draw. Public viewing zones for fans without match tickets were first provided on a large scale at the 2004 European championship in Portugal and became one of the big success stories of the 2006 World Cup. The relatively small size of the Euro 2008 cities -- with only Vienna boasting more than a million inhabitants -- has prompted concern over their ability to handle large numbers of fans. The potential pressure on Switzerland in particular has been increased by the qualification of its three biggest neighbours -- Germany, France and Italy -- although England's failure to reach the tournament should ease the load. The organisers said they would heavily promote the use of public transport in a further effort to reduce congestion in and around the cities. Euro 2008 takes place from June 7 to 29 with matches in Geneva, Berne, Basel, Zurich, Innsbruck, Salzburg, Klagenfurt and Vienna. During the meeting, a senior UEFA source revealed that UEFA has given police a list of 15 matches it suspects may have been fixed. According the source, who spoke to Reuters on condition of anonymity, "15 matches are under investigation and being dealt with by UEFA's disciplinary committee". The matches under suspicion were played in a variety of UEFA competitions including a Euro 2008 qualifier, Champions League qualifiers, UEFA Cup qualifiers and UEFA Cup and Intertoto Cup ties. UEFA would not confirm when the matches took place although a 96-page dossier handed to Interpol last month goes back to July 2005. "I heard about that about an hour ago, for the moment we're looking for what was said by the people, then we'll see what exactly needs to be done. For the moment, I'm not aware of the details," the Euro 2008 COO Martin Kallen told Reuters Television about the potentially huge scandal. Irregular betting patterns on the matches alerted UEFA to the possibility that some may have been fixed.