Police have been called in by medics attacked by pro-life abortion campaigners, as experts warn that social media has made these activists more militant.

It comes ahead of a US-backed campaign that will see vigils held outside 10 UK clinics over the period of lent, for 12 hours a day.

Officers from the Greater Manchester Police met with Marie Stopes abortion clinic staff this month to offer them increased support around a centre in South Manchester and agree a plan with nurses ahead of the 40-day anti-abortion effort in March.

The Birmingham South BPAS abortion clinic also faced protests for the first time in January, prompting concerned staff to schedule appointments with police and councillors.

A leaked report from the Manchester Marie Stopes International centre, seen by The Telegraph, details the daily abuse faced by the clinic’s staff, who say facing protestors has become part of their daily routines.

Nurses described finding screws in the tyres of their cars and said they were followed and told to “go to hell” in cards posted through the door.