That athletic, unkempt backpacker loaded down with survival gear might be no ordinary tourist or hiker, but could be a Russian spy or saboteur, the Latvian authorities have warned the country’s people.

In its yearly threat assessment, Latvia’s Defense Intelligence and Security Service analyzed Russia’s war in Ukraine, discussed China’s geopolitical ambitions, and, yes, alerted the population to be on the lookout for infiltrators sent by the Kremlin, or its closest ally, Belarus.

It’s not clear how great the threat is of saboteurs or spies crossing the borders, but the warning shows the anxiety, heightened by the war in Ukraine, in a tiny country that was long a part of Moscow’s empire and still views its vastly larger neighbor with distrust and fear. Latvia belongs to NATO, but President Trump has called into question the U.S. commitment to the alliance.

Some of the factors the Latvian threat assessment cites could make it hard to tell a camper or low-budget sightseer from an infiltrator. It says to watch out for groups or individuals who are athletic and disheveled, with poor personal hygiene, military-style haircuts and sporting outfits, or who carry foreign documents or currency or stay in forests or near bodies of water.

But other clues it says to watch for are the sort of thing that might be noticed, with or without government guidance: people who question locals about their political opinions, seem overly interested in or take photos of critical infrastructure, speak a stilted version of Latvian, or have survival gear or radios.

The list goes on: While it says to beware of people with maps and navigation equipment, it also says to look out for people who are poorly oriented to the local terrain. The intelligence service also warned that saboteurs may impersonate employees of groups like the Red Cross or United Nations.