Seven Iranian computer experts linked to the government in Tehran were charged Thursday with cyber attacks against American banks and a dam in New York.
The FBI released mug shots of the men named in the indictment as the charges were announced at a Washington press conference. They worked for private security companies that have performed work for the Iranian government, including the Islamic Revolutionary Guard, officials said.
FBI Director James Comey said the suspects may be out of reach while they are in Iran, but the indictments should have them looking over their shoulder if they travel.
"The world is small and our memories are long," he said. "We never say never."
Forty-six major financial institutions were targeted with distributed denial of service (DDoS) attacks in 2011, 2012 and 2013. That stopped hundreds of thousands of customers from accessing their accounts and cost the businesses millions of dollars, the feds charged.
Targets included Bank of America, the New York Stock Exchange, Capital One and ING and PNC Banks, according to court papers.
"These attacks were relentless. They were systematic. And they were widespread," Attorney General Loretta Lynch said.
The hackers allegedly also broke into the control system for a small dam in the suburbs of New York, the indictment says.
This article originally appeared on NBCNews.com.