 In the middle of the 9th century, China experienced a series of purges of "foreign religions", thus cutting Japan off from the sources of texts.In time, other scripts, particularly Devanagari, replaced in India, while in Eastern South Asia (including Assam, Bengal, Bihar etc), evolved to become the Bengali script, Tirhuta script and Anga script, leaving East Asia as the only region where is still used.There were special forms of Siddhaṃ used in Korea that varied significantly from those used in China and Japan, and there is evidence that Siddhaṃ was written in Central Asia, as well, by the early 7th century.