The Dallas gunman was plotting a major bomb attack, authorities said on Sunday, urging calm as hundreds of people were arrested in weekend protests in US cities over police violence against African-Americans.
Thousands of protesters took to the streets in US cities on Friday after a black extremist shot dead five cops during a peaceful march against police brutality in Texas.
The man suspected of opening fire on police officers in Dallas, killing five and wounding seven others, has been identified as 25-year-old Texas resident Micah Johnson, US media reported Friday.
