Authorities said the Tibetans were picked up Sunday in the northeastern village of Jalbire, near the border with China. The group was transported back to the Nepalese capital Kathmandu.
Tibetans in Nepal have been holding regular demonstrations against the Chinese government since March, when deadly clashes broke out between protesters and Chinese authorities in the Tibetan capital, Lhasa.
About 20,000 Tibetans live in Nepal. More than 100 of them were detained last week for demonstrating for Tibetan freedom outside the Chinese embassy in Kathmandu.
The U.S.-based group Human Rights Watch has accused China of pressuring Nepal to crack down on the Tibetan protests. Beijing denies the charge.
Tibetans have complained of discrimination by the Chinese since Beijing took over Tibet nearly 60 years ago.
Some information for this report was provided by AFP, AP and Reuters.