Chief Craig: Detroit Police Department will remain poised

Amid police and racial tensions across the country, Detroit Police Chief James Craig spoke to the media and the public Friday morning, hours after news broke that five police officers in Dallas had been killed at the end of a protest.

"This [threat] is not new. This just didn't start yesterday. Certainly, there has been a threat against police officers for some time now, whether it's ISIL, or ISIS, or whether it's some radical members of associating themselves with Black Lives Matter, or some other groups - this is not a new threat," he said. "This department has been and will continue to be poised, to address threats; this does not change anything. Certainly we may be in a state of heightened awareness in this period, but we're always in a constant state of preparedness."

Around 9 p.m. Friday, five police officers in Dallas were fatally shot at the end of a protest downtown. Seven other officers and two civilians were also shot, the Dallas mayor said Friday morning.

The protesters had gathered in response to the separate police shootings of two black men earlier this week, Alton Sterling and Philando Castile.

A Minnesota officer on Wednesday fatally shot Philando Castile while he was in a car with a woman and a child in a St. Paul suburb. The aftermath of the shooting was live streamed in a widely shared Facebook video.

A day earlier, Alton Sterling was shot in Louisiana after being pinned to the pavement by two white officers. That, too, was captured on a cellphone video.

"I have the good fortune as the leader of this great police department to have men and women who are constitutional, who do it right. Doesn't mean that we won't make mistakes; mistakes do happen," Craig said. "We embrace those who want to peacefully protest; very important. But what happened last night certainly, in my judgement, can't be attributable to those were protesting. ... There was one suspect who decided to do something very different and I applaud the work of the Dallas Police Department in mitigating that threat."

Dallas Police Chief David Brown blamed "snipers" for the officers' deaths, but it was unclear how many shooters were involved. Authorities initially said three suspects were in custody and a fourth dead, killed by a robot-delivered bomb in a parking garage where he had exchanged fire with officers.

Brown says the suspect expressed anger over recent killings of Sterling and Castile by police. A robotics expert says Dallas police appear to be the first law enforcement agency to use a robot to kill.

Brown told reporters that after hours of failed negotiations and in order to not put any officers in harm's way, his department used a robot to deliver a bomb that killed the suspect. Brown said they saw no other option. A Texas law enforcement official identified the slain suspect as Micah Johnson, 25.

None of the other suspects have been identified, and the police chief said he would not disclose any details about them until authorities were sure everyone involved was in custody.

A total of 12 officers were shot, some from DPD and others with DART police. The attacks made Thursday the deadliest day for U.S. law officers since the Sept. 11, 2001, terrorist attacks, according to The National Law Enforcement Officers Memorial Fund, which tracks on-duty deaths.

The Dallas Police Association is collecting donations for the fallen and injured officers and their families. Anyone who wants to contribute can do so at ATODallas.org.

Other protests across the U.S. on Thursday were peaceful, including in New York, Atlanta, Chicago and Philadelphia. In Minnesota, where Castile was shot, hundreds of protesters marched in the rain from a vigil to the governor's official residence.

President Barack Obama said America is "horrified" by the shootings, which have no possible justification. He called them "vicious, calculated and despicable."

Continue reading here the latest developments out of Dallas

The Associated Press contributed to this report