MPs heard fraudsters claim to be offering refunds to people who have lost money from the cancellation of flights and holidays with Thomas Cook, and have also been targeting others who have never been customers of the company.
Transport Secretary Grant Shapps branded the fraudulent activity "absolutely disgusting", adding that the Government has put messages out warning people to be aware of any scams.
Mr Shapps said: "I was made aware of this yesterday. It's absolutely disgusting that that can happen at this time.
"We've put messages back through the OWL (Online Watch Link) system ... which is the system that emails people, neighbourhood watch, to be on the lookout for these sort of scams.
"I mean obviously for someone that didn't even have a holiday booked it's absolutely ridiculous."
Labour MP Paula Sherriff said one of her constituents had been approached by a scam company posing as Thomas Cook in an attempt to gain access to her credit card details in the wake of the company's collapse.
The Dewsbury MP added: "I am aware of a small number of others, who have been contacted by a person purporting to be someone responsible for refunds on behalf of the Thomas Cook group, asking for their details."
The charity Which? said on Wednesday it had heard "worrying stories" about criminals posing as refund agents for the failed travel agent following the firm's collapse on Monday.
It urged anyone looking to claim back the cost of their flights to contact their bank directly.
Adam French, Which? consumer rights expert, said: "We've heard worrying stories of criminals trying to scam people affected by the collapse of Thomas Cook, so while the messages being sent by some banks might be well-meaning, this flawed approach will only be adding to the confusion customers are facing.
"Our advice is to ignore unsolicited calls and texts, and avoid sharing your card or bank details. Anyone looking to claim back the cost of their flight through their debit or credit card
provider should contact their bank directly themselves."
One Twitter user posted that a friend had received a call from a "Thomas Cook refund agent" that just needed their card details.
David Wilding said: "Just seen this from a friend - lowlife scum are now trying to scam o the back of the Thomas Cook collapse ... (sic)"
Mr Shapps also defended the Government's decision not to bail out Thomas Cook, saying it risked throwing "good money away after bad".
He told MPs: "I have seen it suggested in the papers that the Government should have avoided the collapse with a bailout of up to £250 million.
"Given the perilous state of the business, including the company's own reported £1.5 billion half-year loss reported in May followed by a further profit warning in November, this was simply not the case, with no guarantee that an injection would have secured the future of the company.
"Our concern was we would put £250 million at risk and thrown away good money after bad then still have to pay the cost of this repatriation."
The Civil Aviation Authority (CAA) said it had completed more than 130 flights on Monday and Tuesday, returning almost 30,000 people back to the UK, with 95% flying back on the day of their original Thomas Cook flight.
It added that it was working "around the clock" to bring an estimated 120,000 passengers back to the UK, with 70 flights with seats for 16,500 people planned for Wednesday.