Thousands of jobcentre and benefit office staff have completed a two-day strike over pay.
Staff from the government's biggest department are in dispute over pay
It was the second 48-hour stoppage in protest at an imposed three-year pay deal, which union leaders say works out as an average 1% a year for some staff.
Unions said pickets had been outside Department for Work and Pension (DWP) offices across the country and the strike has been "solidly" supported.
The DWP said all of their offices were open for business as usual.
But the Public and Commercial Services (PCS) union claimed jobcentres and benefit offices were closed, and those that remained open offered little or no service to the public.
A striking worker on a picket line outside a DWP office in central London said: "We perform a vital job in helping the unemployed back into work and paying pensions and benefits to millions - we should be valued for this work".
The pickets said more than half of DWP staff earn less than £17,700 and some as little as £12,500 a year.
The union has called on the department to scrap plans to spend millions of pounds on bonuses and use the money to ensure that all staff receive a pay in line with inflation.
Mark Serwotka, General Secretary of the PCS said: "Support for this latest two-day stoppage has been as strong as the one last year and illustrates the strength of feeling over the imposition of a pitiful pay offer that results in real term pay cuts for some of the lowest-paid in the public sector.
Mr Serwotka said the union wants to reach a negotiated outcome but there is potential for more strike action.
"We want the Government and DWR to recognise the value of their staff and to pay them a decent and fair wage.
A DWP spokesman said the department is confident that services and payments will be maintained despite the strike.
"Two-thirds of our staff are at work. We have had robust contingency plans in place and our priority is to keep business as usual.
"The three-year pay award provides a good deal. For those employers lower down the pay scales during the next three years, the minimum pay increase they will see is 3% a year. Many of the lowest paid at the bottom of the pay scale will be getting, on average, more than 5% a year", he said.