UN workers were among as many as 20 people reportedly killed in northern Afghanistan after a Koran burning protest turned violent.
Demonstrators stormed their compound in the city of Mazar-i-Sharif, opening fire on guards and setting fires.
They had gathered in a mass protest following reports that an American pastor had recently set a copy of the Muslim holy book ablaze in Florida.
Police said the dead included three foreign members of the UN, five Nepalese United Nations guards and three Afghan protesters. Two are said to have been beheaded.
UN officials have been reported saying as many as 20 have died.
Reports said the protests were initially peaceful but turned violent.
Reports said the protests were initially peaceful but turned violent
Other reports said several hundred demonstrators were peacefully protesting against the Koran burning when the violence broke out.
Afghanistan had earlier condemned the "disrespectful and abhorrent" burning of the Koran by evangelical preacher Pastor Wayne Sapp in a Florida church on March 21, calling it an effort to incite tension between religions.
It was carried out under the supervision of Terry Jones, who planned to burn a pile of the holy books last year to mark the anniversary of the 2001 terrorist attacks in New York.
He aborted the move under pressure from world leaders including the US president, who earlier said he condemned the latest violence "in the strongest possible terms".
UN secretary general Ban Ki-moon has also condemned Friday's attacks.
Terry Jones said the incident was "tragic and criminal". "The time has come to hold Islam accountable," he said.