The BBC has been warned it faces a "summer of conflict" over job losses after a first wave of national strike action resulted in flagship news programmes being dropped.

The National Union of Journalists (NUJ) said the walkout – which involved 200 members in Scotland – led to picket lines outside the corporation's offices and studios across the UK.

Locations for the action included BBC Scotland's headquarters at Pacific Quay in Glasgow.

The BBC said it was disappointed with the industrial action over plans to cut posts, which the NUJ claims total 2000, including 17 in news and current affairs north of the Border.

The corporation said the action did not change the fact it had to make significant savings.

Among the casualties of the industrial unrest was tea-time news bulletin Reporting Scotland. There was no sign of its main anchor, Jackie Bird, or any of its other leading newsreaders and it was replaced by a four minute summary of yesterday's news. Newsnight Scotland was also axed last night.

Journalists will "work to rule" for the rest of the week and it is expected the NUJ will re-ballot its members at the corporation in two weeks, as will backstage unions Bectu and Unite.

Good Morning Scotland was not broadcast on Radio Scotland, and was replaced with Radio 5 Live, while the Fred MacAulay, Kaye Adams and John Beattie shows were also not aired.

Instead, there were repeats of the Book Café, Classic Scottish Albums, Edi Stark and compilations of the Adams and MacAulay shows.

Radio 4's Today programme was replaced with pre-recorded features.

Paul Holleran, NUJ organiser in Scotland said: "We don't want a summer of conflict but that is the way we are heading.

"The picket lines were phenomenal, I have never seen anything like it.

"We want to see a moratorium on all job cuts, so we can sit down with Tony Hall [the BBC's new Director General] and discuss a way forward."

Picket lines were mounted outside BBC offices across the UK, including London, Cardiff and Birmingham as well as Glasgow.

The NUJ said 7000 jobs had been cut at the BBC since 2004, while a further 2000 are being lost under cost-saving plans.

James Cook, Scotland correspondent for BBC News and an NUJ member, said more than 100 people were involved in the picket in Glasgow.

He claimed cuts were already affecting programming and job losses were being pushed through too quickly.

Mr Cook said: "It is intellectually incoherent to argue you can make cuts this deep while continuing to increase the number of programmes and keep up the quality.

"It's not just about cuts to colleagues' jobs, people being forced out, it's also about the impact on the licence payer."

A BBC Scotland spokesman said: "We are disappointed the NUJ has gone ahead with the strike and apologise to our audience.

"Industrial action does not alter the fact the BBC has significant savings targets and may have to make a number of compulsory redundancies.

"We have made considerable progress in reducing the need for compulsory redundancies through volunteers, redeployment and cancelling vacant positions and we will continue with these efforts."