Free bets and sign up bonuses are a very common way of attracting new customers to online casino, sports book and poker sites.

Gaming giants Ladbrokes and William Hill have confirmed that they are two of five online operators targeted by the Competition and Markets Authority over suspected breaches of consumer protection law.

A joint probe by the UK Gambling Commission (UKGC) and the Competition and Markets Authority (CMA) launched last October uncovered what the pair call “unfair practices” surrounding free bet offers and sign-up bonuses.