Jihadi fighters are using cruise ships to join extremist battle zones in Syria and Iraq.
Because of recent crackdowns at Turkish airports, Interpol officials say the would-be terrorists book cruise tickets hoping to bypass the West Asian republic.
The new airport security measures keep Islamic extremists from getting closer to the war zones.
Interpol has a program that allows airlines to check passenger information on its databases.
"Originally, our concern about people on cruise ships - dangerous people on cruise ships - really focused on the classic sort of rapist, burglar, or violent criminal," Outgoing Interpol chief Ronald Noble told the Associated Press.
"But as we've gathered data, we've realized that there are more and more reports that people are using cruise ships in order to get to launch pads, if you will - sort of closer to the conflict zones - of Syria and Iraq."
Interpol officials are now working on expanding the program to include cruise lines, banks, and hotels.