In Tibetan Buddhism practiced in the Himalayan regions of India, Nepal, and Bhutan, Buddhist Tantra is most often termed "Vajrayāna" (Tib. རྡོ་རྗེ་ཐེག་པ་, "dorje tekpa", Wyl. "rdo rje theg pa") and "Secret mantra" (Skt. "Guhyamantra", Tib. གསང་སྔགས་, "sang ngak", Wyl. "gsang sngags"). The vajra is a mythical weapon associated with Indra which was said to be indestructible and unbreakable (like a diamond) and extremely powerful (like thunder). Thus, the term is variously translated as Diamond Vehicle, Thunderbolt Vehicle, Indestructible Vehicle and so on.