(CNN) -- Two California prison inmates who authorities say directed members of their respective groups -- a street gang and a transnational organized crime syndicate -- to help them steal $8 million from people's bank accounts were sentenced Wednesday to 25 years in prison.
Angus Brown, 36, and Arman Sharopetrosian, 33, were convicted of leading the ring from California's Avenal State Prison, where they were cellmates in 2009, Assistant U.S. Attorney Joseph McNally said.
The case was one of two major federal indictments targeting the transnational Armenian Power crime group, to which Sharopetrosian belongs and which allegedly has ties to high-level crime figures in Armenia and elsewhere, authorities said.
"(Brown and Sharopetrosian) basically combined their skills to execute the bank fraud," McNally said.
Brown, a street gang member, and Sharopetrosian directed non-imprisoned members of their groups to execute the scheme, in which they'd bribe bank insiders to get people's bank account and personal information, authorities said.
The pair's associates would make out high-dollar checks from those accounts, forge the victims' signatures and then deposit the checks into accounts the conspirators established, prosecutors said.
More than 500 victims in multiple states were targeted for a total of more than $8 million, McNally said.
The conspirators mostly targeted older people, believing them to be less "proficient in checking up on their accounts via the Internet," prosecutors said in court documents.
Brown and Sharopetrosian had been nearing the end of their prison sentences. Brown was serving time for identity theft, and Sharopetrosian was in prison for shooting at an occupied vehicle and carrying a concealed weapon, authorities said.
"The goal ultimately was once those checks were deposited from the bank accounts, their associates on the outside would obtain the cash and split up the proceeds," McNally said.
Sharopetrosian, of Burbank, California, was convicted in March of bank fraud conspiracy, bank fraud and aggravated bank fraud. Brown pleaded guilty in December to conspiracy to commit bank fraud conspiracy, bank fraud and aggravated identity theft.
Sharopetrosian's attorney, Anthony Brooklier, said Wednesday that his client was addicted to heroin at the time, and that the addiction clouded his judgment.
"If feel bad for him and his family. It was a case where he was using drugs at the time, and he wasn't thinking clearly," said Brooklier, who added he intends to appeal his client's sentence.
Brooklier contends that Sharopetrosian was involved for only a portion of the scheme's time line, and that no loss of money is directly attributable to Sharopetrosian.
Brown's attorney, Rob Scott, said he'd also appeal the sentence, arguing that it was too long.
"In California, first-degree murder is 25 years to life in prison. This is bank fraud case, no violence, and here he is getting 25 years, the same (you can get) for murder," Scott said. "Something seems counterintuitive about that."
Sharopetrosian is one of 70 defendants named in a racketeering indictment -- the second major case targeting Armenian Power, authorities said. Most have pleaded guilty, but the rest -- Sharopetrosian and 32 others -- are awaiting trial, McNally said.
Both indictments were unsealed in February 2011.
Members of Armenian Power have a heritage going back to Armenia and other Eastern Bloc countries, and the crime group started as a street gang in East Hollywood, California, in the 1980s, authorities said. Members identify themselves with tattoos, graffiti and gang clothing, but the organization is more concerned with racketeering than controlling "turf," authorities have said.
McNally said the two indictments have significantly disrupted the group.
CNN's Michael Martinez contributed to this story.