BELGRADE, Serbia (AP) — A young woman who was injured in a fatal roof collapse in Serbia died this month, bringing the death toll to 15, doctors said Sunday.

The outer concrete roof of a train station building in the northern city of Novi Sad suddenly fell on November 1, crashing into people sitting or sitting below. Initial 14 people died and three were seriously injured.

The fatal incident triggered a wave of protests against populist authorities. Many in Serbia believe that rampant corruption led to sloppy renovation work and the roof collapse as a result.

The station was originally built in 1964 and renovated twice in recent years as part of a wider deal with Chinese state-owned companies.

Protesters in Novi Sad blocked an intersection outside the train station for several hours on Sunday, saying they would not give up until those responsible for the tragedy were punished. Activists put up a huge poster with a bleeding white dove and red handprints – a message to the populist authorities that they have blood on their hands.

“People died because of corruption, because you (the government) are irresponsible, because you won’t take responsibility,” actress and activist Jelena Stupljanin told the crowd, which chanted “prison” in response. “We will not be cut.”

Protesters are also demanding the release of several activists who were detained at an earlier rally in Novi Sad. The rally earlier this month turned violent after masked hooligans threw flares and stones at the Novi Sad City Hall building. Opposition activists said the riots were staged to discredit the peaceful protest marches.

Authorities promised a thorough investigation and Serbia’s construction minister resigned, but no one was arrested and no charges were laid.