NEW YORK (CNN) -- The FBI has begun interviewing clients of deceased Garden City, New York, lawyer William Parente as part of an investigation into his financial dealings, according to FBI spokesman James Margolin.
Stephanie Parente, 19, was found dead along with her sister and parents in a Baltimore hotel Monday.
Margolin said the investigation was launched at the request of police in Baltimore County, Maryland, where Parente, his wife and their two daughters were found dead in a hotel room earlier this week.
"We're looking into Parente's business interests and whether there's any impropriety there and any crime was committed," Margolin said.
Baltimore County police say Parente, 59, killed his family before committing suicide. There have been allegations of financial impropriety in the course of the investigation, said police spokesman Cpl. Mike Hill at a news conference Wednesday.
A law enforcement source told CNN a cell phone belonging to Parente was recovered in the hotel room where the bodies were found. In an attempt to locate surviving family members, investigators contacted people in the phone's directory, and some of those people said they were Parente's investment clients.
The New York attorney general's office confirmed it received a complaint alleging financial wrongdoing from attorney Bruce Montague of Queens, New York.
CNN spoke with Montague's law partner, Steve Drelich, who said he was speaking on Montague's behalf because Montague is distraught over the death of Parente, whom he considered a personal friend as well as a financial adviser. Drelich confirmed Montague was a client of Parente's, and said the two had known each other about six years and that Montague had been investing with Parente for about that long.
Drelich said Montague's estimated losses in investments with Parente total about $450,000.
Drelich said recently Montague "got nervous and asked [Parente] for his money back," in light of highly publicized scandals involving other investors and financial advisers.
Drelich said when Montague kept asking Parente about the money, he was told "it was in a Canadian bank and [Parente] was having trouble getting the money back."
Montague finally received six checks late last week, Drelich said.
"Four of the six checks bounced. We were told there was no money in the account. ... We were told by the bank that the checks were bouncing," Drelich told CNN. Drelich said he doesn't know the amounts of the two checks that did clear for Montague.
It was not until news broke about the Parente family deaths and apparent murder-suicide investigation that Montague contacted authorities, Drelich said.
But Drelich emphasized that Montague was more upset with the deaths than any financial loss.
"You can always make more money," Drelich said. "But Bruce is devastated about the family. He considered [Parente] a friend, but he's especially concerned about the family."
Drelich said his office received calls from at least five other people who said they invested money with Parente, with callers claiming more than $4 million in total investments with Parente. Drelich said his office referred those callers to the state attorney general's office.
Baltimore County police said Parente killed his wife, Betty, 58, on Sunday, April 19, using "blunt force trauma" and asphyxiation.
Police said he killed his daughter Catherine, 11, around the same time, using the same method.
Later that day, his daughter Stephanie, 19, a Loyola College sophomore, was killed also by blunt force trauma and asphyxiation, according to police. Citing hotel records, police said the room was accessed by its electronic key at around 4 p.m. on Sunday, making it plausible that Stephanie entered the room.
Later that evening, police said, Stephanie's college roommate, worried that she had an exam the next morning and hadn't come home, called the room and spoke to William Parente. Parente told the roommate Stephanie would be spending the night. Police believe she was dead at the time.
Parente died some time later by cutting himself, police said, but would not elaborate further on his death.