Richard Lloyd, the executive director of Which?, has told BBC Radio 5 Live Wonga has been in a "complete shambles, a mess of a credit sector" and "needs sorting out".
He will be among those giving evidence at today's select committee.
We need to see a much more urgent approach to getting the cost - in particular fees and charges that payday lenders hit people with - under control, capped, much tougher rules, much sooner about the way they advertise and the way they deal with people who are applying for their loans.
...They're advertising payday loans as a lifestyle choice.... a lot of costs of a payday loan are hidden away in the terms and conditions ... the way they get people into trouble is hitting people with fees and charges that aren't necessarily there in the advertising.
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Sunday will be dry and largely sunny, although there will be some patchy cloud, mainly across eastern Scotland and eastern England.
County lines crime is to be targeted in a new scheme designed to steer young people and children away from exploitative gangs.
Freezing temperatures, a biting wind and risk of snow into next week