Spot videos capture the violence as 11 policemen are shot, and 4 die, in sniper firing in Dallas

Violence is escalating in the USA. Eleven police officers were shot in Dallas, Texas on Thursday night, four of them being killed. The firing was apparently by snipers, who continued to fight the police even after the killings.

This took place during a demonstration protesting against shootings by opolice fficers in Minnesota and Louisiana this week, according to this report.

Local footage captured what sounds like gunshots and mayhem as the crowds scattered.

Here's a witness describing the scene to CNN.

Two snipers were in custody following a police chase after an officer saw one of the two throw a camouflaged bag into the back of a black Mercedes, according to this updated report.

It was still unclear what relationship the gunmen have to the demonstration.

Here is an image of a police officer who appears to be on one knee, devastated.

Citizens were being helped move out of the area with the help of initiatives like this one.