Police in Missouri have named Darren Wilson as the officer who shot dead unarmed black teenager Michael Brown in Ferguson last weekend.
Police Chief Thomas Jackson announced the name at a press conference this afternoon.
Ferguson police had earlier withheld the name of the officer involved, citing security concerns.
The briefing was held near a convenience store that had been burned amid protests over the shooting last Saturday.
Some of the demonstrations turned violent with looting and riots.
Mr Jackson said he would answer reporters' questions at another briefing later today.