Man killed his mom in Florida for the money, cops say. Now, he's fighting to stay abroad

Thomas Gross was arrested in December by an Israeli International Police unit.
Thomas Gross was arrested in December by an Israeli International Police unit.

A Lakewood Ranch mother had already given her son more than $650,000 before he came to visit her in January 2012. But apparently that wasn't enough, according to detectives investigating the woman's killing.

Detectives believe it was money, according to court documents in the case, that motivated Thomas Gross to stab Ina Gross to death on Jan. 9, 2012.

That morning Thomas Gross called 911 to report he had found his 78-year-old mother dead inside her vehicle in the garage of her home in Riverwalk Hammock community in Lakewood Ranch. But when Manatee County Sheriff's Office deputies arrived at the residence, it was evident that Ina Gross had been murdered.

It wasn't long before detectives realized that Thomas Gross' story wasn't adding up and the evidence began to point at him as the killer, court documents reveal.

Thomas Gross, who is now 64, returned to his home in Israel immediately after her funeral on Jan. 16, 2012, long before detectives were able to build a strong enough case.

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Ina Gross Bradenton Herald

In September 2014, the Manatee County Sheriff's Office did obtain a warrant charging him with murder. Later, a grand jury indicted him on a charge of first-degree murder.

"The likely motive for this offense is financial," Detective Stephen Ives wrote in the 2014 arrest warrant affidavit, which was among court documents unsealed in January after his arrest in Israel.

Israeli police arrested Thomas Gross in December, in the coastal city of Herzliya, where he has a home. Since then, Gross has been held in Israeli custody while fighting extradition back to the Manatee County.

On Monday, he appeared before an Israeli judge, who ruled that Thomas Gross should be sent back to the United States, according to his sister Ellen Gerth. Her brother has 30 days to appeal the decision.

While it will not surprise Gerth if her brother appeals, she remains optimistic that justice will prevail, despite how slow-moving it may be.

Justice "is a necessity, but it doesn't bring the person back," Gerth said. ""It does provide some solace that Tom will be punished."

Ellen Gerth says the arrest of her brother, Thomas Gross, for their mother's murder brings her some sense of relief, but she will never forgive him.

The court records unsealed in January revealed more details than previously made public.

Thomas Gross' father, who died 18 months before, had been a renowned pediatric oncologist, leaving Ina Gross with an estate worth more than $4 million. Thomas Gross and his sisters were set to inherit the money but he had already received a $500,000 advance from his share in 2011. His mother had also loaned him money three times that year, totaling more than $156,000.

"Thomas had a history of financial difficulties, according to his sisters, and is often 'over extended' financially as he lives beyond his means most of the time; describing his income as feast or famine," Detective Ives wrote in the arrest warrant affidavit.

Gross claimed that he went to bed at about 11 p.m. on Jan. 8, 2012, the day before his mother was found dead, and that his mother had planned to wake him up at 3:45 a.m. to take him to the airport to catch his flight back home to Israel, according to affidavit. He told detectives he watched television with his mother before going to bed, even listing the programs he claimed they watched.

A neighbor saw him doing something inside his mother's vehicle inside the garage between 10:30 p.m. and 11:30 p.m., the report states. The engine was running as Gross started to close the garage door but he stopped the door when he saw the neighbor. The neighbor said she could hear the garage door close with the vehicle still running as she made it back to her home.

He claimed to have woken up just before 6 a.m., realized he had overslept and went to wake up Ina Gross. He wasn't alarmed when she wasn't in bed, but told detectives he spotted her body in the garage when he was walking to the guest bedroom to get dressed.

While on the phone with a 911 dispatcher, Gross performed CPR, according to the report. But when he was told to open the front door for paramedics, he claimed to have found the door opened. The detectives questioned how he hadn't noticed the front door open when he first woke up and walked directly pass it.

When a neighbor heard the garage door open, she came outside and saw the paramedics. Gross immediately walked over to the woman and said, "Mom's dead. Mom's murdered and I didn't do it."

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Loved ones comfort each other after learning Ina Gross was found dead in Lakewood Ranch. Bradenton Herald File

Ina Gross had been stabbed to death with a 10-inch blade cheese knife from the knife block in her kitchen. Toxicology reports from her autopsy revealed she had high levels of Ambien, a prescription sleep aid, in her blood and stomach contents. The concentration of the drug was enough to have caused a lethargic and sedation effect, according to the medical examiner.

But detectives learned from Ina Gross' doctor and family that she had never been prescribed Ambien. Investigators could not find the pills in her home, either. Thomas Gross' medical records from Israel revealed that he had been prescribed the drug four times between 2011 and 2012.

Gross could not explain why his mother had vomited Ambien inside her vehicle, either, according to the report. He claimed they had eaten leftovers when they came home from a movie the night before, and that she had a glass of wine while he had some juice. Detective found the glass he drank juice from in the sink, but there was no dirty wine glass. His mother didn't have alcohol in her blood stream, the autopsy also revealed.

Ina Gross had a dog who was very protective and was known to bark whenever anyone approached the door or knocked on it. Her neighbor told detectives she heard Gross' garage door and lanai door open between 3 a.m. and 5 a.m., but said she never heard the dog bark.

Thomas Gross told detectives he had been asleep between 10:45 p.m. and 5:30 a.m., but a forensic analysis of his computer confirmed it had been used around 2:45 a.m.

"There is no evidence of an outside person entering the home and committing this act. It is also quite implausible an outside person could have done so without alerting the victim's dog and therefore Thomas who was sleeping in a nearby bedroom," Ives concluded in the arrest warrant affidavit. "There is also no apparent source for the sedative per the victim's residence, physicians and medical records. The only identified potential source is Thomas Gross."