No. No they are not.
The ONS provide a full explanation of how they come up with the numbers. They are compiled via the Labour Force Survey, which adheres to international definitions of employment and unemployment. There is a lot more information contained in the link above, but the TL/DR version is they ask a lot of people – enough people to be able to make strong estimates for the whole economy – questions about their employment status. The results are then reported as the official numbers. They take account of people taking part in workfare-style schemes and people who have been sanctioned off JSA.
Unemployment is still falling. There are a lot of good questions to ask around the quality and duration of the new jobs being created, but the figures as published are right (or at least as right as they has ever been). There is no conspiracy* between the ONS and the government.
*As an aside, if there is a conspiracy, it’s to make the ONS website the most un-user friendly on the web. It’s horrendous!