Dallas shootings were ‘vicious, calculated and despicable’, says Obama

US president Barack Obama has said that the American people are "horrified" by the shooting of 12 police officers in Dallas, five fatally, in an atrocity that he called "a vicious, calculated and despicable attack on law enforcement".

Mr Obama was joined by a chorus of condemnation of the worst attack on US law enforcement since September 11th, 2001, from across the political spectrum as presidential candidates Hillary Clinton and Donald Trump cancelled events in the attack's wake.

Speaking for the second time in less than 12 hours about gun violence in the US as he visited Poland for a Nato summit, Mr Obama said the police officers had been targeted in the attack and described the "twisted motivations" behind the shootings.

“There is no possible justification for these kinds of attacks or any violence against law enforcement,” he said.

Earlier yesterday, before the attack, he addressed the shootings of black men by police officers in Minnesota and Louisiana earlier this week, saying they were "symptomatic of a broader set of racial disparities that exist in our criminal justice system".

While critical of the slow introduction of police reforms to end divisions between police and the African-American community, Mr Obama said in his earlier comments that his criticism should not be interpreted as condemnation of US law enforcement.

The president, in his later remarks, denounced those who attacked police officers in Dallas while they were protecting demonstrators who were protesting against police actions. “Today is a wrenching reminder of the sacrifices they make for us,” he said of law enforcement officials.

“We also know when people are armed with powerful weapons, unfortunately, it makes attacks like these more deadly and more tragic.”

Mrs Clinton cancelled a scheduled campaign event with vice-president Joe Biden in Scranton, Pennsylvania, yesterday and Mr Trump called off a rally in Miami, Florida, after the attack.

Mr Trump in a statement described the Dallas shootings as “a co-ordinated, premeditated assault on the men and women who keep us safe,” and the deaths in Louisiana and Minnesota as “senseless” and “tragic”, saying they were a reminder of “how much more needs to be done”.

“Our nation has become too divided,” he said. “Too many Americans feel like they’ve lost hope. Crime is harming too many citizens. Racial tensions have gotten worse, not better.”

Mrs Clinton tweeted: “I mourn for the officers shot while doing their sacred duty to protect peaceful protesters, for their families and all who serve with them.”

The highest elected Republican, Paul Ryan, the speaker of the US House of Representatives, called for healing, telling members of congress that both Democrats and Republicans wanted to reduce gun violence and end the police killing of black men.

US attorney general Loretta Lynch called the Dallas attack an “unfathomable tragedy” and appealed for calm, acknowledging that many Americans felt a sense of helplessness, uncertainty and fear after “a week of profound grief and heartbreak and loss”.

Former Illinois Republican congressman Joe Walsh, a talk-show host, tweeted and deleted a post blaming Mr Obama and the Black Lives Matter movement that protests against police shootings of black men for inciting violence.

“This is now war. Watch out Obama,” he tweeted. “Watch out black lives matter punks. Real America is coming after you.” He later tweeted that Obama’s words and the Black Lives Matters’ deeds “have gotten cops killed”.