Red Star fans and players celebrated their 31st league title on Saturday after they beat Proleter 2-1 at the Maracana stadium in Belgrade.
Thousands of fans attended the game and hundreds posed with a tank and rocket launcher placed on display in front of the stadium while flares were let off in the stadium following Red Star's win.
Fans has been allowed to return to football in Serbia since June 1. The Serbian league had taken a three month break due to the coronavirus pandemic.
One of the first countries to allow fans back into stadiums, Serbia has eased its restrictions but are still recommending that people adhere to social distancing.
Serbia so far has recorded 12, 803 coronavirus cases, while 260 people died.