Polish authorities believe a body found floating in a canal Wednesday is that of an Irish soccer fan who came to the country for the European Championship.

Documents were found on the body belonging to 21-year-old James Nolan of Blessington, County Wicklow. He disappeared early Sunday in the northern city of Bydgoszcz, sparking a huge search effort in the city. Authorities are awaiting the arrival of Nolan's father, Jimmy, and other family members later in the day to make a formal identification. ''There is a high probability that this is the body of the man we have been searching for,'' a spokesman for prosecutors, Jan Bednarek, told The Associated Press.

No signs of violence were apparent, deputy chief prosecutor Wlodzimierz Marszalkowski told the AP. Robbery didn't appear to be the motive since 600 zlotys ($200) and a credit card were found on the corpse, he said. An autopsy was planned for Thursday.

The clothing on the body matched a description given by friends of what Nolan was wearing when he went missing, Marszalkowski said. Nolan was in Poland for Euro 2012 to follow Ireland and had been traveling with friends in a rented camper van, and was also registered at a hotel on the city's outskirts. He was last seen visiting local bars after watching televised games in a fan zone Saturday night.