In light of the recent lone wolf attack in Sydney, Australia, the United States State Department issued a worldwide travel alert to its citizens worldwide.

The emergency message, posted on the official website of the US Embassy in Manila, called on its nationals to be vigilant and extra cautious.

“The lone wolf attack in Sydney, Australia on December 15, 2014, resulting in the deaths of two hostages, is a reminder that U.S. citizens should be extra cautious, maintain a very high level of vigilance, and take appropriate steps to enhance their personal security,” the announcement said.

The message came about because analysis of past attacks suggested that US government facilities and other public places might be the next target.

“US citizens abroad should be mindful that terrorist groups and those inspired by them can pose unpredictable threats in public venues. US citizens should remain alert to local conditions and for signs of danger.”

It also urged its citizens traveling abroad to enroll in the State Department’s Smart Traveler Enrollment Program (STEP). Those who are enrolled will receive security-related information about the country to be visited, and helps the government track the enrollee in cases of emergency.