A 14-year-old Atletico Madrid fan died after he hit his head on a wall while leaning out of a moving van in central Madrid on Saturday, emergency services said.
The boy suffered a cardiac arrest and despite efforts to revive him, he was declared dead an hour after the accident occurred at 9:20 pm local time, a source from the Madrid emergency services said.
The teenager was travelling with family and friends when the accident happened.
Madrid's Municipal Police are investigating the incident.
Thousands of fans were celebrating in central Madrid after Atletico won the La Liga title on Saturday for the first time since 2014, while police used reinforcements and drones to contain the crowds.