Dallas gunman wanted to stage larger assault on police: chief

The U.S. military veteran who fatally shot five Dallas police officers last week had prepared to stage a larger assault on law enforcement, possibly with explosives, the city's police chief said on Sunday, citing evidence found in the killer's home.

Instead, the gunman deftly improvised to shoot officers assigned to a demonstration in the Texas city on Thursday evening, Police Chief David Brown told CNN. It was the deadliest day for U.S. law enforcement since the Sept. 11, 2001, attacks.

"We're convinced that this suspect had other plans," Brown said, adding that the recent deaths of two black men at the hands of police in Minnesota and Louisiana led the Texas shooter to "fast-track" his plans and attack on Thursday night.

The sniper, Micah X. Johnson, 25, a black veteran of the war in Afghanistan, took advantage of a spontaneous march that broke out during Thursday night's protest.

He leapfrogged ahead of demonstrators and stopped when he saw an opportunity to take "high ground" from where he could target police, Brown said.

The police chief said a search of Johnson's home had turned up evidence that the gunman had practiced using explosives, suggesting he wanted to use them against law enforcement targets.

Before police delivered a bomb-equipped robot that killed Johnson, he told them he wanted to "kill white people," especially white police, after a string of fatal police shootings of black men in U.S. cities in recent years.

SURPRISE ATTACK ON OFFICERS

Brown said police were caught off guard on Thursday when protesters began marching away from the original demonstration site, and were left exposed to the sniper's fire as they scrambled to block off intersections, Brown said.

Johnson's military training also helped him to shoot and rapidly move to other positions, single-handedly "triangulating" his fire with multiple rounds so that police at first believed there were several shooters.

"We don't normally see this kind of running and shooting from criminal suspects," Brown said.

The shooting spree amplified a turbulent week in the United States, as the issues of race, gun violence and use of lethal force by law enforcement again convulsed the nation.

Even as officials and activists have condemned the shootings and mourned the dead officers, more demonstrations against the use of deadly force by police broke out in several U.S. cities on Saturday, leading to hundreds of arrests.

Twenty-one law enforcement officers were injured during demonstrations in St. Paul, Minnesota, where officers were pelted with rocks, bottles, construction material and fireworks, officials said.

"It's really a disgrace," St. Paul Police Chief Todd Axtell said.

The attacks have also clouded the future of Black Lives Matter, an anti-racism movement that has gained strength after the police killings of African-Americans but has also been criticized for vitriolic social media postings against police, some of them sympathetic to Johnson.

U.S. President Barack Obama, speaking in Madrid as part of a European tour, warned that attacks on police over racial bias would hurt Black Lives Matter, saying there will always be people who make "stupid" or "overgeneralizing" comments.

"Whenever those of us who are concerned about failures of the criminal justice system attack police, you are doing a disservice to the cause," America's first black president told a news conference.

"I don't think you can hold well-meaning activists ... responsible for everything that's uttered at a protest," he said.

On Friday, the government of Bahamas warned its citizens to be careful when visiting U.S. cities, offering the kind of advice, often referred to as "the talk," that black parents typically have with their teenage sons.

"Young males are asked to exercise extreme caution in affected cities in their interactions with the police. Do not be confrontational and cooperate," the Bahamas foreign ministry said in its travel advisory.

Police in Dallas were also questioned over their decision to use a bomb mounted on a robot to kill the gunman while he was holed up after killing the five officers.

INITIALS SCRAWLED IN BLOOD

Brown, the police chief, vigorously defended the tactic, saying he approved the plan to detonate a bomb with "about of pound" of C-4 explosives after two hours of fruitless talks with the suspect, who sang, laughed and taunted police negotiators.

Although police believe Johnson acted alone, "we still have not ruled out whether or not others were complicit," Brown said.

Brown also revealed in the CNN interview that Johnson wrote the letters "RB" in his own blood when engaged in a standoff with police, a mysterious clue that remains under investigation, the Dallas police chief said.

"He wrote some lettering in blood on the walls, which leads us to believe he was wounded on the way up the stairwell," Brown said, adding that police were trying to decipher what RB meant.

(Additional reporting and writing by Jason Lange, Daniel Trotta and David Bailey; Editing by Frank McGurty and Paul Simao)