THE head office of rail workers’ union RMT was closed today amid concerns for staff safety because of a protest outside the building.

RMT general secretary Mike Lynch sent out a circular saying there had been an “escalation of abuse and threatening behaviour” against staff at the office in London.

He said a former employee, supported by friends, had been targeting staff.

Mr Lynch said: “The staff’s trade unions informed me that yesterday, female members of staff were subjected to sexist abuse including heckling over their personal relationships, unfounded accusations/allegations were made against multiple other staff members and posted online, and derogatory remarks were made regarding staff members’ families and upbringing.”

He added that on Saturday an individual allegedly attempted to “violently assault a member of staff entering the workplace.

“That staff member’s photograph, place of work and time of arrival at the workplace had recently been posted online by the protesters in what is just one of many examples of RMT staff members being bullied and harassed online.

“The staff do not believe that these incidents are unrelated.”

It is possible that RMT staff will ballot for industrial action over workplace safety.