Boston Marathon bombing suspect Tamerlan Tsarnaev, who was run over by his brother after a gunfight with police, was named as a victim of gun violence during an event held by Mayors Against Illegal Guns, the anti-gun violence group run by New York City Mayor Michael Bloomberg.

Tsarnaev's name was listed during one of the gun group's "No More Names" bus events in Concord, N.H., where it read the names of the people who have been killed in connection to gun violence, the New Hampshire Union Leader reported Tuesday.

"Some of the loudest shouts came when a reader spoke the name of Tamerlan Tsarnaev, one of the Boston Marathon bombing suspects who was killed in April by police during a gunfight," the Union Leader reported Tuesday.

Several protestors shouted, "He's a terrorist," according to the Union Leader.

Mayors Against Illegal Guns used a list compiled by Slate.com, titled "How Many People Have Been Killed by Guns Since Newtown?" Bloomberg's gun group called the inclusion of Tsarnaev in its list of gun violence victims a mistake and apologized for the error.

"He was absolutely not a victim, his name should have been deleted before the list was provided to a family member for reading and his name should never have been read," Mayors Against Illegal Guns said in a statement to ABC News. "It was a mistake, it should not have happened and we sincerely apologize."

The Slate.com list still includes Tsarnaev's name. But the online magazine did post an explanation for including his name.

Dan Kois, an editor for Slate, wrote Wednesday that Tsarnaev is included in the list because the compilation is a "pure accounting of deaths" regardless of the circumstances.

"The interactive is not a list of 'victims' of gun violence-in fact, the interactive never uses that word, for this very reason. It is a pure accounting of deaths, provided, as our original partner in the project @GunDeaths notes, 'regardless of cause and without comment,'" Kois wrote.

"Tsarnaev makes the list because he was killed by gunfire-the linked story clearly explains that he was a bombing suspect killed by cops in a gunfight. The list also includes other wrongdoers killed by law enforcement, people who committed suicide, people who died in accidents, and people killed by criminals. And it includes Sean Collier, the MIT cop allegedly murdered by the Tsarnaevs," he wrote.