UPDATE APRIL 12: John Warren told 13 Action News in a jailhouse interview at Clark County Detention Center Wednesday that he didn't know a robbery was about to take place in the cab.
Once it happened, he said there was nothing he could do to step in and help the driver.
"I went along with it once it took place because you know I was already in the thick of things," Warren said. "So it didn't make sense to help at that point so I really don't know what to say."
UPDATE ON APRIL 11: The cab driver, Dennis Donohue tells 13 Action News his first thought was to comply and get his attackers off of him when he had a knife pulled on him and he was robbed behind the wheel.
"He dug that knife in there. He let me know, he drew blood, he let me know there was a knife in there... I'd like to think he didn't mean business but I'm pretty sure he did," he says.
Donohue says he had no idea until the three were arrested that they were also wanted in several other robberies and that he had unwittingly become their getaway driver before being attacked.
"You're idiots. You're where you belong," he said of the suspects.
LAS VEGAS (KTNV) -- A father and son duo are behind bars for a series of robberies in early April. Las Vegas police say they carried out at least five robberies including one in a taxi cab.
Surveillance video from inside the cab shows a man police have identified as Steven Warren in the backseat behind the driver. His father John is in the front passenger seat and the third suspect is their friend Matthew Amthor.
Police say you can see the younger Warren lunge forward before putting a knife to the cab driver's throat. That driver is completely unaware that he had allegedly shuttled the men away from their last robbery at a Walgreens on Boulder Highway-one of four retail locations police believe were robbed. Police say they demanded money from the driver at knife point. Police say they stole his phone, $250 and then kicked him out of the cab and took off.
Police say Steven Warren confessed to all of the robberies, telling officers he and his father came to Las Vegas about two months ago from the Grand Canyon. He said they were all addicted to drugs (pain pills and heroin) and that was why they committed the robberies, in most cases using his grandfather's vehicle while staying mostly at the Siegel Suites.
All of the suspects are being held at the Clark County Detention Center and face numerous robbery charges.