LAS VEGAS — The FBI and Secret Service are investigating the hacking of the Las Vegas Sands casino company’s websites, which remained out of service more than a day after they were hijacked.
The company’s corporate home page, as well as the pages of the Italian-themed Venetian and Palazzo casinos in Las Vegas, displayed a screen Wednesday that says the sites are down for maintenance. The hacking also knocked out Las Vegas Sands Corp.’s e-mail service and other internal systems.
Sands spokesman Ron Reese declined to say whether the company is aware of any credit card records being breached, adding that the firm’s core systems were not compromised.
FBI spokeswoman Jenny Shearer confirmed the FBI and Secret Service were investigating.
The Nevada State Gaming Control Board was also investigating the cyberattack.
Sands, run by Boston native Sheldon Adelson, operates the largest casino in the world in the Chinese gambling enclave in Macau. It also owns hotel-casinos in Singapore and Bethlehem, Pa.
The first sign that the company’s systems might have been breached came Monday morning, when the company’s e-mail system went down, Reese said.
The problem resolved itself but returned in the middle of the night. By Tuesday morning, hackers had taken control of all Sands sites, posting what looked like a clip-art collage featuring a map with images of flames where Sands casinos are located, a picture of Adelson posing with Israel Prime Minister Benjamin Netanyahu, and a message condemning the use of weapons of mass destruction.
The hackers also posted employee Social Security numbers and signed their work, ‘‘Anti WMD Team.’’
Adelson, known for having a fiery personality and for donating millions of dollars to conservative super PACs and candidates, has been outspoken in his support for Israel.
In October, he floated the idea of dropping a nuclear bomb on Iran, saying strength was the only thing the country understands.
During a forum at Yeshiva University in New York City, he described what he thought would happen if the United States began negotiations over the country’s nuclear program by launching a strike on the Iranian desert and threatening to bomb Tehran next.