The Suffolk County Grand Jury late last week returned indictments charging a Hyde Park man with the shooting death of 17-year-old Roniel Marc during a gun battle last year, District Attorney Daniel F. Conley announced today.

Indicted for second-degree murder Aug. 12 was KEVIN LOUIS (D.O.B. 7/2/87) of Hyde Park. Louis was also indicted for unlawfully carrying a firearm, unlawful possession of ammunition, and unlawful possession of a firearm as a second offense. Louis is already in custody on high bail for gun offenses and is expected to be arraigned in Suffolk Superior Court on Tuesday.

Also indicted Wednesday was DUHAMEL CASSAGNIOL (D.O.B. 12/1/87) of Milton for unlawful possession of a firearm. Prosecutors allege that Cassagniol possessed and transferred to Marc a handgun that Marc used during the gunfight in which he was killed.

The investigation into Marc’s July 4, 2008, shooting death during an evening gunfight remains open, with additional indictments against other suspects possible at a later date, Conley said.

“No matter the victim, no matter the circumstances, we do not give up on homicide investigations,” Conley said. “Boston Police on the street and Suffolk prosecutors in the grand jury work relentlessly to identify the perpetrators in every single case. We’ll use every tool and every lever to find the truth and prove it in court.”

Evidence developed in the course of the year-long investigation suggests that Louis and Marc engaged one another in a gunfight on Wood Avenue during a July 4 cookout. Prosecutors allege that Louis chased Marc through several back yards and ultimately onto Edwardson Street, where a third gunman is believed to have fired a shot that killed Marc. The identity of that third gunman remains under aggressive investigation by the homicide units of the Boston Police Department and Suffolk DA’s office.

Though he is not alleged to have fired the fatal shot, Louis is charged with Marc’s murder under the same theory used to convict MANUEL ANDRADE for the 2007 homicide of Chiara Levin in Dorchester – that he took part in a shootout in a public place and is responsible for the death that ensued as a result.

“Where the defendant chooses to engage in a gun battle with another with the intent to kill or do grievous bodily harm and a third party is killed, the defendant may be held liable for the homicide even if it was the defendant’s opponent who fired the fatal shot,” the Supreme Judicial Court of Massachusetts wrote in its 1997 decision on Commonwealth v. Felix Santiago.

Louis is represented by attorney Christopher Belezos. He is expected to face arraignment for Marc’s murder on Aug. 18.