Interpol on Tuesday issued "red notices" seeking the arrest of seven fugitives wanted for "environmental crimes" from illegal logging to elephant poaching.
The rare appeal by the international police organisation based in Lyon, France, comes ahead of World Environment Day on Wednesday.
"We've highlighted seven criminals wanted in various countries... for environmental crimes," Interpol executive director Tim Morris told AFP, adding that the crimes included illegal logging, poaching and trafficking in ivory.
"Interpol is calling on the global community: these people must live somewhere, they must travel, they must commute, they must socialise. Someone knows where they are and we're asking the public to help bring these people to justice," Morris said.
The appeal names the suspects, who are wanted variously by China, Kenya, Greece and eSwatini, the former Swaziland.
"We know environmental crimes generate huge amounts of money, between $100 and 300 billion (90 and 260 billion euros) a year," Morris said. "There's money laundering, corruption, and also financial crime, violence and murders all associated with environmental crime."
Interpol, the world's largest international police organisation, works with its 194 member countries to coordinate policing across the planet, notably on organised crime and counter-terrorism operations.