A Baltimore cop was acquitted of all charges Monday in connection with the controversial death of Freddie Gray last year.

Mayor Stephanie Rawlings-Blake immediately called for calm in the city, which has been rocked by rioting, looting and arson in the wake of Gray’s death.

Police Officer Edward Nero, 30, had been charged with second-degree assault, reckless endangerment and two counts of misconduct for allegedly helping to arrest Gray without probable cause and then acting negligently by also failing to make sure he was buckled in a police van April 12, 2015.

Angry protesters outside the courthouse react:



Gray’s neck was broken during the transport while he was handcuffed and shackled. The 25-year-old man died a week later.

Nero — a former New Jersey volunteer firefighter — was one of six Baltimore cops charged in the case. He opted against a jury trial and put his fate in the hands of Baltimore City Circuit Court Judge Barry G. Williams.

The judge said prosecutors didn’t show Nero acted unreasonably — and that the cop didn’t handcuff Gray.

An emotional Nero wiped his eyes and hugged his lawyers after the verdict was read.

About a dozen protesters were outside the courthouse and chanted, “No justice, no peace!” after Williams ruled.

One protester called the verdict “a complete slap in the face to blacks in America.”

The mayor asked city residents to respect the judge’s verdict.

“This is our American system of justice,” she tweeted. “We once again ask the citizens to be patient and to allow the entire process to come to a conclusion.”

The mayor added: “We will protect our neighborhoods, our businesses and the people of our city.”

James Pasco, executive director of the National Fraternal Order of Police, said prosecutor Marilyn Mosby should have never charged Nero.

“The district attorney didn’t just overcharge — she mischarged in this case,” Pasco said. “She should be referred to the bar association for sanctions. It was always our expectation that the officer would get cleared because there was no legal basis to charge him.”

Gray’s death in police custody sparked rioting in Charm City.

Three of the officers in the case are black, and three, including Nero, are white.

Nero was the second officer to stand trial. He faced the lesser of the charges, all misdemeanors.

His lawyers argued that he wasn’t the one who made the arrest and that it was the police van driver who should have buckled Gray in if necessary.

The trial of Officer William Porter, who was charged with manslaughter in the case, ended with a hung jury.

Baltimore City Councilman Brandon Scott said Monday’s verdict didn’t surprise — or particularly trouble — him.

“This was not the big fish, so to speak,” Scott told WBAL-AM. “When you look at this officer [and his actions], it seems this is more of a civil thing than a criminal thing. ”

He urged citizens to remain calm and pointed out there are four more trials to come.

“This is not over,” Scott said. “We just have to let justice play out. ”

With Post wires