Bridgnorth Cliff Railway implemented a strict face covering policy to protect its passengers and elderly staff upon reopening in August.
The new measures were soon met with confrontation from people refusing to wear the protective gear and follow Covid restrictions.
Following the intervention of police, owners said the matter subsided.
But staff are now using panic buttons, CCTV and walkie-talkies after claims they are again being targeted by "activists and thugs" who have become "aggressive and violent".
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Cliff railway owner, Dr Malvern Tipping, said the railway is working with the police and will consider issuing lifetime bans to those involved.
Dr Tipping said: "These people have paid no regard to social distancing rules. Instead they have pushed through roped-off areas and barged past passenger queues to confront staff.
"In the last week the harassment of staff has been intensified with activists screaming abuse and posting photographs of them on social media with abusive language peppered with expletives.
"Our initial suspicions that the aggression arising around face masks was being perpetrated by outsiders and non-passengers have been confirmed. Staff have given to our general manager the names of the two individuals who been abusive towards them before posting abusive rants and pictures of our staff on social media."
It comes after an anti-face mask protest took place under Bridgnorth Town Hall last Thursday.
Dr Tipping added: "These people have been confirmed as not being genuine passengers, but as activists connected with the anti-face mask protest which took place under Bridgnorth Town Hall.
“Unfortunately, there are covid deniers, anti-mask activists and anti-vaxxers across the country.
“During the pandemic we will do our best to offer a service to all our passengers, able-bodied and disabled alike. Once this pandemic is over – and it may take some time – we look forward to welcoming them all to a resumed normal service."
Due to the railway being a public passenger service, staff are deemed frontline workers. The railway confirmed all incidents will be reported to the police.
West Mercia Police Chief Inspector Mark Reilly said: “We work very closely with the owner of Bridgnorth Cliff Railway and are in regular contact with them, any potential issues are always discussed with the local sergeants.
"At this time we have received no reports of violent or threatening behaviour at the premises or reports of anti-face mask protestors being at the site."