A Miami businessman is suing Bank of America over $90,000 he says was stolen from his online banking account in a case that highlights the thorny question of who is responsible when a customer's computer is hacked into.

Joe Lopez, 42, said in a complaint filed Thursday in Circuit Court in Miami that Bank of America was negligent and failed to protect him from online banking risks it knew about.

Lopez is asking to recover the money lost, plus interest and attorney fees. "For Bank of America, $90,000 is peanuts," Lopez said. "For me, it’s my world. The bank has turned its back on me."

The complaint is believed to be the first legal action by a customer against a U.S. bank to recover money apparently stolen by cybercriminals.

Avivah Litan, an expert on online fraud for Gartner Inc., a Stamford, Conn.-based research firm, called it "a landmark case."

“This exposes all the holes in the system," Litan said.

"Banks technically aren't responsible for what happens on your PC. But banks can't reasonably expect consumers to protect themselves from cybercriminals."

Litan expects that future cases like Lopez's will eventually pressure banks into adopting stricter security measures for online banking.

The U.S. Secret Service, which investigates computer-based attacks on banks, sent Lopez a letter in November saying its "initial examination" had determined that a variant of a virus called coreflood had existed on his computer systems.

The letter noted that coreflood is malicious software code that can give an attacker remote access to the infected system, but it did not explicitly say coreflood was the cause of the loss.

Internet security experts have estimated that one-third to half of all cybercrimes originate in Russia, Eastern Europe and the Baltic nations, where organized crime is believed to be orchestrating many of the attacks.