Pentagon urges vigilance from U.S. troops on IS's "hit list"

The Pentagon has over the weekend notified its 100 service members to remain vigilant after they appeared on an online "hit list" compiled by a group supportive of the extremist group -- the Islamic State (IS).

"Vigilance and force protection considerations remain a priority for commanders and their personnel," said a statement by U.S. Marine Corps Lieutenant Colonel John Caldwell.

"It is recommended Marines and family members check their online footprint, ensuring privacy settings are adjusted to limit the amount of available personal information," the statement added.

Personal information of the 100 U.S. service members was posted online on Saturday by a previously unknown group which called itself the "Islamic State Hacking Division." The group said it got the names, addresses and photos of the 100 service members by hacking military database and called on its backers to kill those U.S. service members.

However, Pentagon officials said the information appeared to be drawn from public sources, including Facebook pages and media interviews.

U.S. Homeland Security chief Jeh Johnson had earlier warned that extremist groups, such as the IS, were effectively using social media to reach into communities in other countries and inspire independent actors to conduct violence. Endite