Thousands of metalworkers walked off their jobs Monday in Turin, Italy, and marched through the city to demand more workplace safety measures after four colleagues died in a factory blaze last week, the Associated Press reports.

The fire broke out early Thursday at German steel-maker ThyssenKrupp's plant in the northern industrial city. Flags were flying at half-staff in Turin, where three workers are still hospitalized in serious condition. Metalworkers staged an eight-hour protest strike.

Government officials responded to the accident by pledging to hire more workplace safety inspectors and to stiffen sanctions for violations.

Workers demonstrated in downtown Turin carrying banners protesting workplace accidents, led by the crying father of one of the fire victims.

Survivors of the blaze have claimed that emergency training and maintenance of fire extinguishers had been lacking since the company decided to shut down the plant by September 2008 and transfer production to Terni, in central Italy.

ThyssenKrupp AG in Terni said in a statement Sunday there was "no confirmation" that any safety violations had played a role in the blaze.

Italy has one of the worst workplace safety records of the six founding members of the European Union, with 984 reported dead in workplace accidents since January, according to Thomson Financial News.