In the wake of Thursday’s terrorist attack in Nice, France the U.S. Embassy in Paris is urging American citizens be vigilant, exercise caution at large gatherings and take steps to “bolster their personal security.”

“Authorities believe the likelihood of terror attacks in Europe will continue as European members of ISIL (Da’esh) return from Syria and Iraq,” the Embassy said. In addition, there is “a continuing threat in Europe from unaffiliated persons planning attacks inspired by major terrorist organizations but conducted on an individual basis.”

The increasingly hostile terrorist attacks throughout the region, including November’s attacks in Paris, March’s attack at Brussels airport, and the bombing at Turkey’s Ataturk hub in June, have many wondering if it is safe to travel to Europe at all

“Europe is no stranger to terrorism, having experienced national terrorist groups, such as the IRA and ETA over the decades,” Caroline Bremner, head of travel at research firm Euromonitor International said in May. “However, the Paris attacks perpetrated by IS revealed the indiscriminate nature of this new form of terrorism that aims to destroy the very heart of European values, such as freedom and culture.”

Extreme acts of violence have an immediate impact on tourism, with “short, sharp declines” in the aftermath, according to Euromonitor data. France has already seen a countrywide decline of 8 percent in arrivals in January in the wake of last fall’s deadly coordinated attacks.

What steps can travelers take to improve their personal security?

The Embassy has urged U.S. citizens in Nice to contact family members immediately and to check local press for the latest updates and guidance from local authorities.

While the Government of France is not restricting public gatherings at this time, the U.S. Embassy is cautioning travelers against attending “demonstrations and large events intended to be peaceful can turn confrontational”– including any protests or marches– that can be viewed as targets by terrorists.