Violent protests left at least five dead and others wounded Wednesday as demonstrations over Quran burning intensified in Afghanistan.

Police killed four people and wounded 10 others during protests in Parwan province, said Abdul Wassi Sayedkhili, a provincial council official. Health officials said a fifth person died and 10 others wounded in eastern Nangarhar province.

The Qurans were among religious materials removed from a detainee facility at Bagram Airfield. The materials were gathered for disposal and were inadvertently given to troops for burning, Gen. John Allen, commander of NATO’s International Security Assistance Force, said Tuesday.

A military official said the materials were removed from the detainee center’s library because they had “extremist inscriptions” on them and there was “an appearance that these documents were being used to facilitate extremist communications.”

The U.S. Embassy in Kabul went into lockdown as the protests entered a second day Wednesday.

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