Updated

Pakistan says its archrival India is building a "secret nuclear city" to produce thermonuclear weapons as well as developing intercontinental missiles and secretly stockpiling nuclear material.

Foreign Ministry spokesman Nafees Zakaria made the allegations at a press conference Thursday, without providing evidence or further details. Indian officials could not immediately be reached for comment.

Tensions have soared between the South Asian rivals in recent months over violence in the disputed Kashmir region, which is split between Indian and Pakistani zones of control and claimed in its entirety by both. The two nuclear-armed countries have fought two of their three wars over Kashmir.