Prosecutors in the US said on Monday that as many as 4,000 people in the Manhattan area of New York used ATMs to steal around $15m from the Municipal Credit Union (MCU) bank, which suffered computer network damage in the 11 September terrorist attacks.
In what is being described as the largest fraud to come out of the attacks, 66 people have already been arrested and the police are searching for 35 others.
Many more are under investigation, according to New York County District Attorney, Robert Morgenthau.
Because of the system's fouled up security, the fraudsters found a way to repeatedly withdraw up to $500 a day from the bank's cash machines, even if they did not have enough money in their accounts.
The breach happened when the attacks on the World Trade Center damaged a nearby building housing MCU's computer systems.
MCU officials soon realised that there was a problem but did not stop withdrawals in case they offended customers affected by the attack.
"This is a prime example of no bad deed goes unpunished. People took advantage," said Morgenthau.
He confirmed as many as 4,000 people manipulated the system to overdraw their accounts by at least $1,000. More than 540 MCU customers exceeded their balances by $5,000.
The person who took the most was a 54 year-old nurse who made 54 cash withdrawals from 18 September to the end of October, running up an overdraft of $18,111.
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