Editor's note: This story has been updated with additional comment.

DALLAS — Texas Gov. Greg Abbott praised the work of Dallas officials for demonstrating great heroism against the lone assassin who shot 11 police officers, killing five during what was a peaceful rally Thursday evening to protest aggressive policing across the nation.

"The past 24 hours in Dallas has been a veritable tale of two cities," said Abbott who returned to Texas early from an out-of-state trip to appear at Dallas City Hall with area and state lawmakers including Dallas Mayor Mike Rawlings and Texas Attorney General Ken Paxton. "It has been the tale of heroism of police officers. At the same time it has been a tale of cowardice by an assassin."

Abbott went on at length about the support the state has for its police officers.

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"For every man and woman of the Dallas Police Department as well as any officer in the state of Texas I want you to know you have the respect of a grateful state," Abbott said. "And you have a governor who has your back."

Abbott, often a fierce critic of President Obama, thanked him for reaching out to Texas immediately.

"And I want to express my gratitude to the White House that reached out to contact me," Abbott said. "Because of the president's trip, we were unable to make an official connection, but he did want to express his sorrow and grief for the people and law enforcement in Dallas, but also any assistance that he could provide."

The White House announced Friday afternoon that Obama will visit Dallas early next week.

Despite Abbott's call for unity, several Texas Republicans released statements Friday that seemed to conflict with his message. In an interview on Fox News, Lt. Gov. Dan Patrick said he blamed the Black Lives Matter movement for the shooting, and called the protesters "hypocrites" for expecting officers to defend them when shots were fired.

Asked about Patrick's comments, Abbott repeated his call for unity and said Texans should be grateful for law enforcement because "they played the role we hope law enforcement officers will play, and that is run towards danger to save lives."

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"Understand that this should not be used as a tool of division, but instead we can use what happened here in Dallas for good," Abbott added. "We can find purpose in every single challenge that occurs. I can find purpose in what happened in Dallas, Texas and one of those purposes is working for greater unity in Dallas and Texas."

Rawlings thanked the governor for his assistance and support and revealed that the shooter killed by a police robotic bomb earlier in the day, Micah Xavier Johnson, 25, was the lone gunman responsible for shooting all 11 officers: 10 Dallas Police Department officers and a single officer from the Dallas Area Rapid Transit Authority. All were acting as security during a rally that attracted hundreds to downtown to protest the police violence in Louisiana and Minnesota this week that claimed two citizens lives. 

Rawlings, who earlier in the day insisted that neither he nor Dallas Police Chief David Brown would comment on other suspects or even utter the shooter's name, gave into reporter's questions about other people the police department detained overnight.

Rawlings said that 20 individuals — all wearing camouflage clothing — were apprehended initially because they ran when gunfire began. None are in custody now.