Corey Stewart, chairman of Donald Trump’s Virginia and chair of the Prince William County Board of Supervisors.

The chairman of Donald Trump’s Virginia campaign on Friday placed responsibility for a police massacre in Dallas on Democratic presidential hopeful Hillary Clinton and another Democrat, Virginia Lt. Gov. Ralph Northam.

Prince William Board of County Supervisors Chairman Corey A. Stewart (R), who like Northam is planning to run for governor in 2017, posted an article about Thursday’s slayings on Facebook early Friday, along with this comment:

“Liberal politicians who label police as racists — specifically Hillary Clinton and Virginia Lt. Governor Ralph Northam — are to blame for essentially encouraging the murder of these police officers tonight.”

Trump’s campaign disavowed the post, issuing a statement through John Fredericks, host of a conservative radio talk show and vice chairman of Trump’s Virginia campaign.

At least five police officers were killed in Dallas and seven were wounded July 7 after a peaceful protest over recent police shootings. Here's what we know so far. (Deirdra O'Regan/The Washington Post)

“Corey Stewart’s comments are his own,” Fredericks said. “They have nothing to do with the Trump campaign. They are not reflective of Mr. Trump’s position, nor are they indicative of Mr. Trump’s personal value system on the horrific events in Dallas and the last several days, with so many people killed. Today, Mr. Trump offers his thoughts and prayers for all of the victims’ families. And everyone in the Trump campaign is praying for our brave police officers and first responders who risk their lives to protect us.”

Stewart’s Facebook post — and a second post later in the day — did not cite any specific statements by Clinton, who has criticized recent shootings of black men by police, or Northam.

In the past, Trump has suggested that anti-police rhetoric could trigger attacks on officers. But the presumptive Republican presidential nominee did not repeat that view on Friday, instead offering support for police and referring in his own Facebook post to the “senseless, tragic deaths of two people in Louisiana and Minnesota”: presumably Alton Sterling, who was fatally shot by police in Baton Rouge; and Philando Castile, killed by an officer in a suburb of Minneapolis.

Stewart stood by his comments in a written statement to The Washington Post.

“The simple fact is the irresponsible rhetoric of left wing politicians and the media contributed to the events in Dallas last night,” he said. “There is an entire subset of our culture claiming police are the enemy and pushing a lie that there is a ‘war on minorities.’ Obama, Hillary, and Northam need to denounce this hateful rhetoric.”

He repeated his allegations against Clinton and Northam with a second Facebook post Friday.

“Va. Lt. Governor Ralph Northam and Hillary Clinton are pitting minorities against the police,” he said. “Whenever there is a police shooting involving a minority, their knee jerk reaction is to allege racism. That is insulting to the men and women in blue who risk their lives to protect ours. But worse, these allegations result in the murder of our police.”

Clinton’s campaign declined to comment on Stewart’s Facebook posts.

In response to the Dallas killings, the presumptive Democratic presidential nominee wrote on Twitter, “I mourn for the officers shot while doing their sacred duty to protect peaceful protesters, for their families & all who serve with them.”

Clinton had issued a series of statements in recent days in response to the shootings of Sterling and Castile, suggesting that racism had played a role in their deaths.

“Something is profoundly wrong when so many Americans have reason to believe that our country doesn’t consider them as precious as others because of the color of their skin,” she said Thursday on Twitter before the Dallas shootings.

Northam had not made any public comments about the Louisiana and Minnesota shootings until sending an email to The Post in response to Stewart’s Facebook comment.

“With so much violence and tragedy in Dallas, Minneapolis and Baton Rogue, this is a time for our nation to come together and heal,” Northam said in the email. “There is no place in this commonwealth for this divisive rhetoric, which only serves to politicize a national tragedy.”