The Brookhaven Town website remains shut down today after hackers replaced the contents with pro-Islamic State group propaganda.

"We want to find out if this is a prank, or if this was something serious -- if this was ISIS," says Brookhaven Supervisor Ed Romaine, who ordered the site taken down after the incident.

On Sunday, a group calling itself "Team System DZ" appeared to have breached the site. The town says that no proprietary information was taken, and the intruders accessed the website but did not seize control over it.

The group left a statement including, "You will be held accountable Trump, you and all your people for every drop of blood flowing in Muslim countries. I love Islamic State."

Brookhaven officials say the hack was not on a readily accessible portion of site -- so few people saw it -- and that no important data was stolen.

Security experts say this breach is a wakeup call for local governments and their technology departments that hackers are targeting them.

"They are thumbing their nose and saying, hey, we got in, and you didn't stop us," says Tino Posillico, of Farmingdale State College.

Similar hacks targeted more than 70 other websites around the world, including government sites in Ohio. Rep. Lee Zeldin, of Shirley, weighed in.

"I have been in touch with Brookhaven Town Deputy Supervisor and Councilman Dan Panico and offered to assist in any way possible with regards to securing necessary support and resources from the federal government," Zeldin said.