Criminal gangs will likely attempt to get their hands on supplies of new Covid-19 vaccines, international police organization Interpol warned, potentially disrupting supplies of the crucial shots as they become available.

The agency issued a global orange notice—which it describes as a serious and imminent threat to public safety—to its 194 members, calling the vaccines “liquid gold,” and warned counterfeit vaccines or coronavirus tests could become a growing problem as international travel gradually resumes in the months to come.

“As governments are preparing to roll out vaccines, criminal organizations are planning to infiltrate or disrupt supply chains,” Interpol Secretary-General Jürgen Stock said late Wednesday. “It is essential that law enforcement is as prepared as possible for what will be an onslaught of all types of criminal activity linked to the Covid-19 vaccine.”