DOHA, Qatar — Belgian cyclist Frederiek Nolf was found dead in his Doha hotel room Thursday, hours before the start of the fifth stage of the Tour of Qatar.

The 21-year-old Nolf was found dead in his bed by his roommate Kristof Gooddaert, the Belgian cycling team Topsport Vlaanderen Mercator said. The cause of death wasn’t immediately known.

“We had dinner together last night,” team director Jean-Pierre Heyderrickx told reporters, holding back tears. “He was absolutely fine. He was joking and in a good mood.”

The team quit the Qatar tour and planned to return to Belgium.

The final stage of the tour will take place on Friday as planned, the Qatar Cycling Federation said in a statement. Thursday’s fifth stage was shortened and results were not noted.

Team manager Christophe Sercu told Belgium’s VRT television that each rider on the team is tested every four months for doping and Nolf was drug free. Nolf made his professional debut with Topsport Vlaanderen Mercator last year.

Topsport is one of the 17 teams taking part in the six-day Tour of Qatar, which ends Friday.