The first arrests have been made in connection with alleged fraud relating to the Eat Out to Help Out scheme.
HM Revenue and Customs (HMRC) officers visited addresses in the London area and arrested three men aged 43, 48 and 37 on suspicion of cheating the public revenue and fraud by false representation yesterday (3 November).
They have all been questioned and released under investigation.
Kath Doyle, deputy director of the fraud investigation service at HMRC, said: "The vast majority of businesses will have used Eat Out to Help Out responsibly, but we will not hesitate to act where we suspect abuse of the scheme.
"This is taxpayers' money and any claim that proves to be fraudulent limits our ability to support people and deprives public services of essential funding."
The Eat Out to Help Out scheme ran throughout August and gave diners a government-backed 50% discount on food and soft drinks of up to £10 on Mondays, Tuesdays and Wednesdays.
In early September the Treasury said 84,700 hospitality venues had signed up and made around 130,000 claims worth £522m.
HMRC has launched a disclosure facility where businesses who have been overpaid or were not eligible for the scheme can make a repayment.