Vietnam reported a record number of wildcat strikes last year because of demands for salary hikes prompted by soaring inflation, dpa quoted authorities as saying Thursday. A total of 857 wildcat strikes were recorded in the first 11 months of 2011, double the figure for all of 2010, according to statistics from the Ministry of Labour, Invalids and Social Affairs. Strikes increased not only because of inflation but also because many companies did not abide by labour laws, including not signing labour contracts with staff; failing to pay social insurance; and not offering leave to employees, ministry officials said. The shortage of labour at many industrial estates led employees to believe that they would not be fired for striking. Strikes require permission from authorities, but all strikes recorded last year were illegal strikes. Seventy-five per cent of these wildcat strikes took place at companies with an element of foreign investment. The government wanted to limit inflation last year to 7 per cent, but it hit 18.6 per cent, the highest level in Asia, because of rising prices for food, housing and transport. Wildcat strikes have been on the rise in Vietnam since 2006. The country recorded 422 in 2010 and 218 strikes in 2009.