On Edge: Dallas SWAT officers stormed a parking garage near police headquarters last night in response to a report of a “suspicious person” dressed in black. The department announced it had received a threat that had to be taken seriously, but they found nothing.

Black Lives: As Dallas mourns its five dead police officers, another casualty of the Friday night ambush just might be the Black Lives Matter Movement, which is being blamed for inflaming hatred of the police.

The National Association of Police Organizations posted on Facebook that, “We must also stand up and speak out against the senseless agitators and gutless politicians who helped bring about these murders.”

Texas Lt. Gov. Dan Patrick told Fox News Friday, “I do blame former Black Lives Matter protests — last night was peaceful, but others have not been.”

The Black Lives Movement, violent at times, was spawned from police killings of unarmed black men. Now some critics of the movement have gone so far as to blame President Obama. A top official in the St. Louis Police Association posted, “THIS BLOOD IS ON YOUR HANDS, MR. PRESIDENT.”

While police organizations express rightful outrage at the killing of five Dallas cops, they tend to remain silent when their fellow officers wrongfully kill members of the public. The Black Lives movement was beginning to convince the broad public of the danger faced by black Americans when they are confronted by the police.

Charles Blow writes in the NY Times, “This is a time when communities, institutions, movements and even nations are tested. Will the people of moral clarity, good character and righteous cause be able to drown out the chorus of voices that seek to use each dead body as a societal wedge?”

Blow continues, “Will the people who see both the protests over police killings and the killings of police officers as fundamentally about the value of life rise above those who see political opportunity in this arms race of atrocities?”

The Obit Page: Sidney Schanberg, the Pulitzer-winning NY Times reporter who stayed behind in Cambodia when it fell to the Khmer Rouge in 1975 and who, with his assistant Dith Pran, inspired the movie “The Killing Fields,” has died at age 82.

His Times Obituary says, “Mr. Schanberg was a nearly ideal foreign correspondent: a risk-taking adventurer who distrusted officials, relied on himself in a war zone and wrote vividly of political and military tyrants and of the suffering and death of their victims with the passion of an eyewitness to history.”

Schanberg and Dith came close to being killed by the Khmer Rouge. Schanberg got out of the country, but Dith was swept into the Cambodian holocaust. He survived to become a photographer for the Times, and died in 2008 at age 65.

Set Point: Serena Williams beat German Angelique Kerber at Wimbledon yesterday to win her 22^nd Grand Slam singles title and tie the record set by Steffi Graf.

Social Notes: Former New York Yankee Derek Jeter, who in a long bachelorhood dated some of the most beautiful women in America, married model Hannah Davis yesterday in Napa, Calif. He’s 42, she’s 26. Some of the Sports Illustrated swimsuit models Jeter hasn’t dated were guests — “Morning Joe” co-hosts Joe Scarborough and Mika Brzezinski were seen jetting off to Nantucket together. They say they’re just good friends — Former Daily show host Jon Stewart and his wife Tracey have adopted a pair of pigs.

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