Investigators are trying to figure out how the intruders gained access to the Bank of America account. The account has been frozen and all of the city's money has been temporarily moved out of Bank of America as a precaution.

Numerous other small town, municipalities and small businesses have been victimized by similar online heists over the past three or four years.

In most incidents, the cybercrooks first stole usernames and passwords used by to gain access to bank accounts. The stolen credentials were then used to log into the online accounts and wire transfer money to mule accounts in the United States and abroad.

The FBI has estimated that U.S. businesses and banks have lost hundreds of millions of dollars due to such thefts in recent years.

The Burlington theft came just days after security firm RSA warned of cybercriminals plotting a massive and concerted campaign to steal money from the online accounts of thousands of consumers at 30 or more major U.S. banks.