SKOPJE, North Macedonia (AP) — Thousands of people protested Monday outside the government headquarters in North Macedonia 's capital, Skopje, over allegations that patients at a state cancer hospital missed life-saving treatment because staff were stealing the expensive drugs to sell on the black market.

Chanting “Murderers,” demonstrators demanded the resignation of the country's health minister and the hospital management. Among the protesters were several people who said their relatives had died after being given placebos instead of proper chemotherapy because the drugs had been stolen.

“My mother had breast cancer and her condition worsened a week after she was admitted to the clinic," one young man told the crowd. “Unfortunately, she didn’t survive.” The man, who didn't give his name, described the hospital's alleged behavior “monstrous.”

The government and hospital officials have sought to assure the public that cancer patients are not at risk, while prosecutors have launched an investigation into the claims.

Prime Minister Dimitar Kovachevski said Monday that he “understands the anger and indignation of the people,” but added that the entire state health system should not be blamed.

The scandal broke several months ago, following a string of media reports into the alleged scheme. In May, police arrested a nurse at the Skopje hospital who was allegedly caught on CCTV smuggling cancer drugs out of the building, and accused her of stealing them for sale on the black market.

On Friday, police raided the hospital and the homes of two staff members, seizing documents, computers and data drives. No arrests were made and no charges have been filed.

Health Minister Fatmir Mexhiti and hospital director Violeta Klisarova told reporters in Skopje Monday that “patients are safe and there is no manipulation with the therapy.”

Klisarova said that since the nurse's arrest hospital protocols have been revised and staff access to cancer drugs has been restricted.

“I will do everything in my power to clear up this case,” said Mexhiti, adding that "The ministry will work closely with law enforcement to ensure a thorough and impartial investigation."

North Macedonia’s President Stevo Pendarovski voiced hope Monday that the investigation would lead to “appropriate punishment” of those found guilty, adding that the state health system has failed the public.

“It is high time that the system confirms we are capable of dealing with severe forms of organized crime and corruption, and of ending the culture of impunity for serious violations of the laws,” Pendarovski's office said in a statement.

The conservative main opposition party, VMRO-DPMNE, called for the government to resign — a demand it has been pressing for months due to a dispute over proposed constitutional changes that would expand the official list of ethnic minorities in the country.