British Airways has suspended 17 staff for making “inappropriate comments” on a website aimed at bullying pilots prepared to break a threatened cabin crew strike.

A BA spokesman said: “Inappropriate comments have been posted on a union website and we have asked Unite for their assistance in removing those postings and identifying those individuals involved.”

“We will not tolerate intimidation of our staff and any reports of staff being threatened will be investigated. A number of staff have been suspended while we carry out investigations.”

Unite is midway way through a fresh balllot of 13,500 cabin crew, after a 12-day strike over Christmas was declared unlawful by the High Court.

BA has been training volunteers to replace striking crew in the event of a walk-out after the ballot closes on February 22.

Unite said the suspension of 17 cabin crew members was “in no way as a result of comments they are alleged to have posted on a union website”.

“It is Unite’s clear view that BA’s actions are in relation to alleged comments made on Facebook,” the union said.

“BA has unleashed a cyberspace witch-hunt,” Len McCluskey, Unite’s assistant general secretary, told The Times. “Cabin crew have been suspended simply for being a Facebook friend. This is McCarthyism for the internet age.”

The scandal emerges as BA chief executive Willie Walsh trains volunteers from across the company to “keep BA flying” during a strike.

Unite claimed that only 216 people responded to the call for volunteers, but BA has declined to confirm the exact number.

Unite has promised no action will be taken over the Easter holiday if this ballot succeeds, following the public outcry when a 12-day walk-out over the Christmas-New Year holiday was called.

The strike was halted after a judge ruled the ballot invalid because a small proportion of those who voted were people taking voluntary redundancy.