On Saturday, Birdi was remanded to ten days judicial custody by the chief judicial magistrate in Srinagar and subsequently he was shifted to the high-security central jail.
Official sources said that Birdi complained of chest pain today morning and he was immediately shifted to the hospital by jail authorities.
Zahid Farooq Sheikh, the 17-year old schoolboy, had been shot by a BSF trooper on February 5 in the Nishat area of the capital city, triggering public outrage and protests across the valley.
The police had earlier arrested BSF trooper Lakhwinder Kumar, who admitted during questioning that he had shot at the youth, but maintained he did so on the orders of his commanding officer Birdi.
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