In July, a 22-year-old South End man became the first person to be charged in an alleged scheme to steal money from a charity established for victims of the Boston Marathon bombings.
On Thursday, Attorney General Martha Coakley’s office said Branden Mattier had help from his older brother, Domunique Grice, 27, in the plot to bilk The One Fund Boston by filing a claim on behalf of a relative who died more than 10 years ago.
A Suffolk County grand jury indicted the brothers Thursday on larceny and fraud charges.
An arraignment date in Suffolk Superior Court has not been set.
“These defendants allegedly orchestrated a scheme to defraud The One Fund of more than $2 million, money that was donated by many generous people and intended for the real victims of the Marathon attack,” Coakley said in a statement.
Mattier’s lawyer did not return a call seeking comment.
It was not known if Grice had hired a lawyer.
According to prosecutors, the siblings concocted a claim on behalf of an aunt who had supposedly lost both of her legs in the April 15 attacks. However, the aunt died more than a decade before the bombings, officials said.
Coakley’s office said Thursday that the brothers attended a private ceremonial closing in June of a memorial erected in Copley Square for the bombing victims, as well as a complimentary dinner for victims and their families at the Seaport Hotel.
Investigators also found that Mattier and Grice had scheduled an appointment to test drive a new Mercedes-Benz E350 on the same day that a check for $2.195 million from The One Fund was expected to arrive.
The check came, but it was a ruse.
An undercover state trooper delivered it to Mattier outside his home July 2, and he was arrested soon after receiving the phony payout, officials have said.
A not-guilty plea was entered on his behalf at an earlier arraignment in the case in Boston Municipal Court.
Mattier is being held on $20,000 cash bail, Coakley’s office said.
Grice is not in custody and will be issued a summons to appear at his arraignment, authorities said.
A spokeswoman for Coakley declined to say if prosecutors plan to request that Grice be held on bail at his arraignment.
A telephone number listed for Grice was disconnected on Thursday.
The brothers are not the only defendants facing charges for alleged One Fund scams.
Earlier this month, prosecutors announced charges against a Linden, N.J., woman who allegedly filed a bogus application detailing injuries that she claimed to have suffered in the bombings.
In July, a woman from Troy, N.Y., was arrested on charges alleging that she collected $480,000 from The One Fund after filing a false claim that she suffered a traumatic brain injury in the attacks.Travis Andersen can be reached at travis.andersen@
globe.com. Follow him on Twitter @TAGlobe.