 -- The death of Freddie Gray has been ruled by the medical examiner's office a homicide caused by severe trauma.

State's Attorney Marilyn Mosby, the chief prosecutor for Baltimore, announced this morning that her office has also found probable cause to pursue criminal charges in connection to the case.

Officers Caesar Goodson Jr., (top left) William Porter (top center), Edward Nero (below left) and Garrett Miller (below center), Lt. Brian Rice (top right), and Sgt. Alicia White (below right) were arrested and charged in Gray's death.

Michael Davey, the attorney hired by one of the officers, spoke on behalf of all six, saying “these officers will be vindicated because they have done nothing wrong.”

“No officer injured Mr. Gray, caused harm to Mr. Gray, and [they] are truly saddened by his death,” Davey said during a news conference this afternoon with the police union.

Mosby announced a series of charges facing the six police officers involved in putting Gray in custody and transporting him in the police van on the morning of April 12. The charges vary for each individual, but include several counts of manslaughter, second-degree assault, misconduct in office and false imprisonment, among others. The most serious charge she listed was second-degree depraved heart murder, which only Goodson faces. All were released this evening after posting bond.

Gray, 25, was taken into police custody in Baltimore April 12 and sustained a spinal injury during that time requiring medical attention. He went into a coma several days later and died a week after his apprehension. Police have never said why they took him into custody, noting only that he ran from officers, and they have not publicly explained how Gray received the spinal injury.

Mosby detailed the findings of her office's independent investigation into Gray's apprehension, and she detailed how officers are alleged to have repeatedly ignored Gray's pleas for help and that officers allegedly bound his arms behind his back and put his legs in clamps but did not secure him within the police wagon with a seat belt, which is a violation of Baltimore police policy.

One of the biggest findings that Mosby announced was that the decision to take Gray into custody in the first place was unwarranted because the knife that he had is allowed under Baltimore laws. While the knife was able to fold, it was not a switchblade.

Mosby urged calm in the wake of the charges, speaking directly to protesters at the end of her news conference.

"I heard your call for 'no justice, no peace.' However your peace is sincerely needed as I work to deliver justice on behalf of Freddie Gray," she said.

In an open letter today before Mosby's news conference, the Baltimore City Fraternal Order of Police asked Mosby to appoint a special independent prosecutor.

"I have full faith in your professional integrity. While I have the utmost respect for you and your office, I have very deep concerns about the many conflicts of interest presented by your office conducting an investigation in this case," the statement read. "These conflicts include your personal and professional relationship with Gray family attorney, William Murphy and the lead prosecutor’s connections with members of the local media."

President Obama commented on the charges shortly after they were announced, though avoided going into the details of the case because it remains open.

“It is absolutely vital that the truth comes out about what happened to Mr. Freddie Gray,” Obama said.

“I can tell you that justice needs to be served, all the evidence needs to be presented. Those individuals who are charged obviously are also entitled to due process and rule of law. I want to make sure that our legal system runs the way it should,” he said, noting that the U.S. Attorney General’s office is in communication with authorities in Baltimore.

“What I think the people of Baltimore want more than anything else is the truth,” he said. “That’s what people around the country expect.”

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