"He hired them as temporary workers but after they had moved jobs or left New Zealand, Singh continued to use their IRD numbers to put through portions of his permanent staff's wages," Mr Goggin said.
"He logged some of the permanent staff's wages under the IRD numbers of the temporary workers who no longer worked for him.
"This means, by using the wrong IRD numbers, Singh could have helped his permanent staff to defraud the system by effectively reducing their declared income," Mr Goggin said.
This could have led to staff members getting more family assistance tax credits than they were entitled to, or reducing the amount of child support they may have had to pay, he said.
"Singh could also have misused the numbers to employ and pay illegal immigrants."
Mr Goggin said Inland Revenue was contacted by a handful of backpackers concerned they had been taxed on money they had not earned.
"We acted quickly to stop Singh and help the additional 120 victims we also identified whose IRD numbers were likely to have been misused," said Mr Goggin.
He said where applicable, Inland Revenue had refunded overpaid tax.
"Some backpackers whose IRD numbers were ripped off are worried they won't be able to return to New Zealand due to Singh's actions causing possible breaches to their work visa," Mr Goggin said.
Inland Revenue had since recovered the $262,458 Singh owed.