Employees of the centre for emergency medical help in Sofia on January 8 went on protest and relay hunger strike.
They accuse the director of depriving them of extra pay because of denunciations.
A meeting was held at the health ministry late last week and an inquiry has been assigned.
The protest was organised by “Zashtita” (Protection) trade union.
"Те нямат глас, но имат нас": Стотици излязоха на протест срещу жестокостта над животните