The office of the Nigeria Labour Congress in Kaduna State has been invaded by armed thugs numbering about 100 on Wednesday.
The office is the meeting point of workers in the state who are protesting the sacking of their colleagues by the state government.
The Police Public Relations Officer, ASP Muhammad Jalige confirmed the arrest of 20 of the thugs who invaded the office, Dailytrust reports.
Thugs had also yesterday tried to disrupt the activities of the protesters by hurling stones at them before they were chased away by security operatives.
The protest held at the NEPA roundabout along Ahmadu Bello Way later continued after the attack.