Students stopping traffic, stand in silence during ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)

People stopping traffic, stand in silence during ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)

People stopping traffic, stand in silence during ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)

People stopping traffic, stand in silence during ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)

A student holds students certificate and stands in silence during ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)

A student holds a banner and stands in silence during ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)

A woman stands in front of the University building where students are camping in ongoing protests that erupted after a concrete canopy fell last month and killed 15 people, in Belgrade, Serbia, Friday, Dec. 20, 2024. (AP Photo/Darko Vojinovic)