Officials in New Haven say hackers stole more than $6 million from the city in a series of cyberattacks.

City leaders say it appears the hackers got access to the email account of the chief operating officer for New Haven's public schools in late May.

Authorities say in total, six fraudulent payments were made.

"To date we have been able to recover $3.6 million," says New Haven Mayor Justin Elicker. "So, $3.6 million of the over $6 million that was stolen is back in city accounts. The FBI has also been able to freeze additional money."

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A retired FBI agent says this type of crime is called a business email compromise. He says that's where a criminal impersonates someone, like a financial person, in hopes of tricking someone else into sending them money.

The FBI and New Haven police are investigating the matter.