Labour has been accused of attempting to cover up the scale of England's illegal traveller site problem after the number of caravans parked in unauthorised camps hit a new record high.Official figures released today showed that the number of caravans parked without planning permission rose by 23 per cent in the year to January and now account for almost a fifth (17 per cent) of all encampments.The number of the residential vehicles parked on land not owned by travellers also rose by 81 per cent, while the overall total in England has also passed 29,000, the most documented since records began in 1979.It comes amid rising anger at cases where travellers have purchased land, often in leafy parts of the Home Counties, before swooping to lay tarmac and create pitches at weekends and on Bank Holidays when council officials are not around.They have then sought planning permission retrospectively, forcing local authorities to take legal action to kick them off an area already built over, in a frequently lengthy and costly process.But at the same time the government has unveiled plans to collect less data about sites.The Ministry of Housing, Communities and Local Government has announced it plans to make the official Count of Traveller Caravans a single annual event, instead of doing it twice a year as it does currently.It has insisted that unauthorised traveller sites are local councils' problem. Shadow communities secretary James Cleverly said: 'On Labour's watch, the number of traveller caravans on illegal sites is soaring and encampments on other people's land are up by a staggering 81 per cent. And Labour are trying to cover it up.