Six Baltimore police officers were indicted Thursday in connection with the death of Freddie Gray, a 25-year-old who suffered a fatal spine injury while in police custody, touching off a wave of protests and riots across parts of the city last month.

The expected grand jury action leaves the most significant ­charges in the case unchanged, including a second-degree murder count against one officer and involuntary manslaughter ­charges against that officer and three others. The indictment means that the case will move out of the lower District Court and into Circuit Court.

Baltimore State’s Attorney Marilyn J. Mosby, who filed charges against the officers May 1, said at a news conference Thursday that prosecutors presented evidence in the case to the grand jury over two weeks. As a result, the grand jury added a charge of reckless endangerment against each of the officers.

Mosby initially had charged three of the six officers with false imprisonment in connection with what she said was the illegal arrest of Gray. However, the indictment does not include any false imprisonment counts, meaning that those charges are no longer part of the cases.

Baltimore State’s Atorney Marilyn J. Mosby announced charges against the six police offices on May 1. (Alex Brandon/AP)

A grand jury — which meets behind closed doors and hears from prosecutors, not defense lawyers — usually follows prosecutors’ recommendations when preparing an indictment. The absence of the false imprisonment counts suggests that Mosby chose not to pursue those charges. She did not comment on that at the news conference.

Gray was arrested after police chased him and found that he was carrying a folding knife. When Mosby initially filed the false imprisonment charges­ against the three officers involved in the arrest, she noted that the type of knife that Gray was carrying was legal in Maryland. But to gain a conviction for false imprisonment, prosecutors would have had to prove that the officers knew the knife was legal but decided to arrest Gray anyway — that they had a “specific intent” to unlawfully detain him.

Three of the officers also initially had been charged with two counts each of second-degree assault. The indictment accuses them of only one count each.

Charges were initially filed on May 1 against officers Caesar R. Goodson Jr., William G. Porter, Edward N. Nero and Garrett E. Miller, Sgt. Alicia D. White and Lt. Brian W. Rice.

Goodson faces the most serious charges­ — second-degree ­depraved-heart murder, involuntary manslaughter and assault, among other counts. Porter, Rice and White each face involuntary manslaughter and other charges. Nero and Miller face charges that include assault. All six also are charged with misconduct in office.

The officers are expected to be arraigned July 2 in Baltimore Circuit Court, which could mean making their first public appearances before a judge. They each are free after posting bail set by a court commissioner after they surrendered May 1. After an indictment, when a criminal matter moves from District to Circuit Court, a judge usually reviews a defendant’s bail and could adjust it based on any new or dropped charges.

Typically prosecutors and defense attorneys wait until after indictments to begin filing motions that outline their cases. But in this high-profile case, the sides already have begun to lay out their positions, arguing in court over the legality of Gray’s arrest and allegations of conflict of interest involving the city’s top prosecutors.

Also Thursday, federal authorities released a series of wanted posters, seeking to identify people believed to have intentionally set fires in looted stores and on the streets during overnight rioting that began shortly after Gray’s April 27 funeral.

Screenshots from surveillance video cameras show at least seven men inside stores or on the streets near North and Pennsylvania avenues in West Baltimore, where large crowds clashed with police. The photos were made public by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

Authorities say Gray, who lived in Gilmor Homes, a public housing complex in West Baltimore’s Sandtown-Winchester neighborhood, was injured after he was arrested on April 12.

A video of his arrest shows officers on top of him locking his legs in a brace, and then dragging his seemingly limp body to the back of a police transport van. But police believe that he was injured during the 45 minutes he spent unsecured in the back of the van, shackled at the wrists and ankles.

Baltimore’s police commissioner, Anthony W. Batts, has said the officers who transported Gray violated several policies, including failing to secure him with a seat belt in the van and repeatedly failing to get him medical attention he requested. The officer who drove the van stopped a few times, including to check on Gray, to put him in leg shackles and to pick up a second prisoner at another arrest site.

It was after one of these stops — at Baker and Mount streets — that prosecutors say in charging documents that “Mr. Gray suffered a severe and critical neck injury as a result of being handcuffed, shackled by his feet and unrestrained in the back of a BPD wagon.”

Gray died at a hospital April 19. The U.S. Justice Department is conducting a civil rights investigation into the death, as well as a broader review of patterns and practices of the Baltimore Police Department.

The union representing Baltimore police officers and attorneys for the individual officers have lashed out against the charges­­ and Mosby, accusing her of several conflicts of interests — her husband is a City Council member who represents the district in which Gray was arrested. They also say she rushed her investigation and charged the officers to quell the unrest, which they contend benefited her and her husband’s political ambitions.

Attorneys for the officers filed a voluminous motion contending that statements such as the ones Mosby made during her May 1 announcement went beyond mere recitation of the criminal charges and laid bare biases showing that she was trying to placate hostilities and elevate her own stature. They also have noted that the lawyer for the Gray family once represented Mosby on an attorney grievance issue. Those attorneys are calling for Mosby to be removed from the case.

Mosby’s office has countered in court, calling the accusations desperate and an attempt to hijack the grand jury process.