Civil Servants Strike Over Pensions Row
Unions have warned of more strikes as tens of thousands of public sector employees, including police, prison officers and lecturers, took to the streets.
More than 20,000 off-duty police officers - who are prohibited by law from striking - marched through central London saying job cuts were putting public safety at risk.
The officers donned caps that read: "Cuts are criminal," as they protested against the cuts and changes to their pensions and pay.
They said they were marching to highlight "the unprecedented attack on policing by this Government and the consequences that these cuts will have for public safety".
Policing Minister Nick Herbert wrote an open letter to all police saying he is "impressed by the work you do for your communities".
But he insisted difficult decisions on pay and pensions are needed and added that police pensions will still be among the best available.
Prisons, jobcentres, colleges, military sites and Government offices were also affected by the walkout, which is the third national day of action in the past six months over planned changes to pensions, which would see increased worker contributions.
The general secretary of the Unite union, Len McCluskey, described the day as "a fantastic success".
"There will be more strikes in June, at the end of the summer, the winter, next spring and on and on and on," he said.
"We need to make it clear that the coalition of resistance we have with groupssuch as students and senior citizens is generating momentum."
Union leaders told Sky News that up to 80% of UK prisons were hit by the prison officer protest.
By law, prison officers are also not allowed to strike, so they held protest meetings at jails across England, Wales and Scotland as a show of solidarity.
The move meant prisoners were staying behind bars for extended periods without attention and affected the judicial process, with those accused of committing crimes not being transported to court.
Prison worker Andy Spalding told Sky News: "We're unhappy because we're being asked to do more work for longer - and get less at the end of the day.
"I can't dispute that we do get a good pension, but we work for it. We're doing a very difficult job in very difficult conditions."
The Ministry of Justice said in a statement it is disappointed by what it described as "unlawful action".
The Government claimed only 100,000 civil servants had taken part in the "futile" strike, but unions said over 400,000 workers had been involved.
Mark Serwotka, leader of the Public and Commercial Services (PCS) union, said Government claims some people would be better off after the reforms were a lie, adding it would press for another national strike in June.
Rail union leader Bob Crow's call for a national strike in October was well received by the crowd, while London bus workers are due to vote on strikes in a row over payments during the Olympic Games.
A spokesman for Prime Minister David Cameron said: "We have come up with a fair plan, which is fair to the tax payer as well as the public sector worker."
Cabinet Office minister Francis Maude described the strike as "futile" and insisted talks over pensions will not be reopened.
Despite the action, the Government made it clear in the Queen's Speech that the changes would go ahead.