The US State Department has taken the rare step of issuing a global travel alert for US citizens traveling overseas.
Citing recent terror attacks in France and Mali and the bombing of a Russian plane in Egypt, it said terror groups including the Islamic State, al-Qaeda and Boko Haram ‘continue to plan terrorist attacks in multiple regions.’
It also says there is a real possibility of ‘lone wolf’ attacks.
"There is a continuing threat from unaffiliated persons planning attacks inspired by major terrorist organizations but conducted on an individual basis."
It is cautioning US citizens to exercise vigilance at large public events and on public transportation.
The alert does not specify which countries or regions are more likely to be targeted but the warning is in effect for the next three months.
"Be aware of immediate surroundings and avoid large crowds or crowded places. Exercise particular caution during the holiday season and at holiday festivals or events," it said.
No advisory has been issued for domestic travel but Transportation and Security Administration officials said security had been beefed up ahead of the busy Thanksgiving holiday period.
TSA agents will screen 40% more passengers and there are in excess of 900 TSA canine teams being deployed at airports.
