Thich Nhat Hanh, the revered Zen Buddhist monk who helped pioneer the concept of mindfulness in the West and socially engaged Buddhism in the East has died. He was 95.

A post on the monk’s verified Twitter page attributed to The International Plum Village Community of Engaged Buddhism said that Nhat Hanh, known as Thay to his followers, died at Tu Hieu Temple in Hue, Vietnam.