CNN) -- An international manhunt was under way Thursday for a New Zealand couple who fled after a bank mistakenly paid them NZ$10 million (US$6 million) when they applied for a loan of just NZ$10,000.

New Zealand authorities said they had sought help from Interpol in locating the couple who disappeared May 7, two days after an employee error at Westpac bank paid them 1,000 times the amount they asked for.

The accidental millionaires, who have not been identified by authorities but are believed to come from the resort of Rotorua, were thought to have left the country, police said.

"At this time I am not prepared to disclose the amount of money involved, name the individuals or business involved, or discuss which country the individuals may be in right now," said Detective Senior Sergeant David Harvey of the New Zealand police.

Local media identified the couple as Leo Gao and Australian girlfriend Cara Young, adding that they are now believed to be in China.

The bank, too, would only say it was "pursuing vigorous criminal and civil action to recover a sum of money stolen."

However, local media and many Rotorua residents were abuzz about the amount.

TVNZ, a CNN television affiliate, said the couple applied for a NZ$ 10,000 (US$ 6,000) loan for a service station they owned.

On or about May 5, the bank erroneously put NZ$ 10 million (US$ 6 million) into their bank account. The next day, the service station closed its doors. And the day after, the couple went missing, TVNZ said.

"Saturday, Sunday, we realized something else was up," Rotorua resident Tania Davies told the station. "They'd done a runner."

Another resident, Chevi Lambert, said a private investigator came by asking about the couple over the weekend.

"It's such a big world, he could just disappear," Lambert said.

Police said the bank had recovered part of the money, indicating the couple may not have been able to access the entire amount.