Sayfullo Saipov to be sentenced to life in prison in West Side bike path terror attack after jury unable to reach unanimous death penalty decision

A verdict was reached Monday in the penalty phase of the trial of convicted West Side bike path attacker Sayfullo Saipov.

The jury of 12 was unable to reach a unanimous verdict, so the 35-year-old will be sentenced to life in prison without release.

He was convicted of killing eight people and injuring a dozen on the bike path in 2017, all in the name of ISIS.

The jury of nine men and three women did not want to talk about the verdict outside the courthouse on Monday. They deliberated for nearly nine hours.

On the verdict sheet they indicated they could not agree about whether he was likely to commit criminal acts of violence in the future. Seven indicated they felt like prison was a better punishment.

On Halloween in 2017, Saipov drove a rental truck onto the bike path, killing eight bicyclists on Halloween in 2017. They were five friends from Argentina, a mother of two from Belgium, a 23-year-old New York City man, and a 32-year-old from New Jersey.

Saipov told the FBI he intended to continue on to the Brooklyn Bridge but crashed into a school bus, got out and ran waving around fake guns. He was eventually shot by an NYPD officer.

He asked to fly the ISIS flag in his hospital room.

A dozen people were injured, including a woman who had to have both legs amputated.

The jury convicted him in January of murder in support of terror organization during the liability phase.

During the penalty phase, they saw photos of the bodies of the eight victims, some on the bike path. They heard from family of the victims who testified about the impact of their loved ones' loss on their own lives.

Survivors spoke about their injuries and recurring fears. Some said they struggle to find the will to keep going.

The court also heard from Saipov's family, flown in from Uzbekistan with special permission to testify as the defense argued for life in prison without release in an attempt to show he had a tight-knit family and a normal life before he began consuming ISIS propaganda when he moved to the U.S.

His wife and three young children, who live in the U.S., were not in the courtroom.

The jury followed along with instructions -- a checklist -- guiding them on what the prosecution had to prove for the death penalty, things whether defendant committed his attack after substantial planning and premeditation, and whether he killed or attempted to kill more than one person in a single criminal episode.

In the end, though, it was a moral decision up to each juror.

"I think it's the verdict most related with what we are going through -- survivors, victims families. Also, it is a life sentence. We, our injuries, losses, will not come back," injured Belgian survivor Aristide Melissas said by phone.

Melissas testified on the stand about how his life was impacted by the terror attack. His wife was the survivor who had to have both legs amputated.

Saipov will be formally sentenced at a later date.

Watch live updates streaming around the clock on CBS News New York.

The penalty phase is essentially a second trial. Jurors heard more about each of the eight people killed and the impact of their losses. Prosecutors noted one man's child barely spoke a word for an entire year after his father's murder. 

Saipov, 35, was convicted of killing a group of five friends from Argentina, a woman from Belgium, a man from New York City and a man from New Jersey on Oct. 31, 2017. He sped down the West Side Highway bike path in a rented truck, picked off bicyclists and ultimately crashed into a school bus before a police officer shot him. About a dozen more people were injured. 

Saipov did it in the name of becoming a member of ISIS. 

Prosecutors arguing for the death penalty told the court Saipov "continues to pose a threat" and has screamed at prison guards about "slitting their throats." They asked the jury to "impose a sentence of death ... not because it's easy, but because it's appropriate."

The defense admitted Saipov has "not been a model prisoner," but said the threats were just talk and asked the jury to "choose life," noting Saipov will die in prison no matter what.  

 A defense attorney shared photos of Saipov's children and large family in Uzbekistan with CBS2. 

Saipov was convicted last month on all counts against him, including murder and providing material support to ISIS. The jury deliberated just six hours over two days.

Saipov rented a truck from Home Depot in Passaic, New Jersey. He drove the 6,000 pound vehicle along the West Side Highway and veered onto the bike path, mowing down bicyclists. 

Ann-Laure Decadt, in New York from Belgium with her two sisters and mother on a celebratory trip, was killed. Her sister testified. 

"Her gaze was lifeless. She just stared up into the air and there was lots of blood coming out of her mouth," she said. 

Ten friends from Argentina were riding bikes in pairs. All five on the left side were killed. 

Survivor Martin Marro testified a friend "positioned my head so I wasn't drowning in my own blood."

Darren Drake from New Jersey was struck and run over. 

Nicholas Cleves from New York was killed. His mother held her head in her hands in court when his lifeless body under a sheet was shown in court.

Twelve people were injured. 

Marion Van Reeth from Belgium took the stand. She woke up in the hospital two weeks later with no memory of what happened. Among her many injuries - both legs were amputated, and a finger. 

Another woman on a bike testified he missed her by an inch but she saw him one person then three more. 

"Boom, boom boom. They went up in the air. Their bicycles went up in the air. They came crashing down," she testified. 

Saipov intended to keep driving to the Brooklyn Bridge, but hit a pole and a school bus, injuring a child and adult on board. He got out waving fake guns. A police officer shot him. 

Investigators found knives and sheets of paper in his vehicle - a confession. 

He asked to fly an ISIS flag in his hospital room, and proudly smiled while boasting to the FBI about what he'd done and why he chose Halloween, 2017 - because he knew it would be crowded - and the West Side bike path "because it was easy." 

A prison notebook seized last year had ISIS drawings. He called himself "a soldier of the caliphate" during a phone call to his mother from prison. 

The defense admitted he did, believing he was "doing God's will," and he continues to believe that. So they did not cross-examine any witness or survivor.

They argued he did it for religious reasons, saying he was a supporter of ISIS, not a member, merely watching general videos in encrypted chats with no actual connection to the group. 

They say the married father of three previously worked as a long-haul truck driver and Uber driver, and during that time began consuming ISIS propaganda on his phone. They presented no case - did not call any witnesses. 

An expert who studies jihadist groups testified for the prosecution that there are two ways to become a member of ISIS: Travel overseas, or commit an attack where you are. The defense countered that Saipov planned to die during the attack, so he couldn't have been trying to become a member. The expert said you're identified the same when the terror group claims responsibility, as a soldier of the Islamic state, or as a martyr for them if you're killed. 

Saipov did not testify.