Sabir (20) and Valindan (21) had gone for trekking along with their friends but took a different route on the way back and haven't been seen since, a police official said.
"The two have not been spotted since August 21. A search of the entire trek route was started today but there is no clue," he said.
Police said a group of 32 foreigners went for trekking to Triund on August 19. Some local trekkers and porters were also accompanying them.