The growing fury was noted by Hartman in his tweets before his confrontation.
"Getting reports of journalists being attacked all over Cairo," he tweeted Wednesday.
Hartman and Abi-hanna headed for the airport today to collect equipment that had been impounded upon their arrival Tuesday. After collecting their gear, Hartman tweeted, "Cairo Airport security had to hold back a spitting mad man who was shouting at one of my colleagues about media bias against the govt."
In today's incident, Hartman said the two-car convoy was stopped at one of the many makeshift checkpoints that have sprung up around Cairo, most of them created by neighborhood groups to protect themselves from looters.
Their drivers were forced into the back seats and one man tried to snatch a camera from the car, but it was grabbed back. Men from the checkpoint drove them down "a dusty, beat up street where some people opened up the dinged-up barricades and drove us down to a dingy little cul de sac," Hartman said.
A large banner of Mubarak hung over the street and dozens of men were standing around, Hartman said.
"Then they directed our driver to take us down a dark, narrow alleyway. A man sitting next to me with a cigarette dropping ashes on my shoulder.... No way, we can't go down this alley, I told our driver, and he turned off the car."
The two vehicles were quickly engulfed by men who poured out of the alley.
"It gradually escalated, the tension and anger in their voice.... It was pretty clear we were in a threatening situation. People were making gestures and putting their fingers under my throat" and making a slitting motion, he said.
"A man in police uniform came up to me and said, 'So help me God.... I am going to cut off your head,'" Hartman recalled.
One man was yelling, "Cut their necks now, cut their necks now," and another pointed an imaginary machine gun at Hartman and made shooting noises.
"I couldn't see outside the windows except angry faces and the gestures. I thought we were absolutely doomed," Hartman said.
They were saved, he said, when Abi-hanna "lunged forward and gave a great big bear hug" to a man who appeared to be an elder of the neighborhood. "He gave him a kiss on each cheek and told the man referring to me, 'He is my guest. He is your guest in this country. Egyptian people are better than this."
Hartman said the cameraman appealed to the "renowned generosity of the Egyptian people."
Abi-hanna's words "seemed to calm the tensions down" enough for them to get the cars in gear and escape, despite the efforts of some to stop them.
Hartman said that through it all, none of their equipment was stolen and they were not punched or physically abused.
Reporters for other news outlets, including NBC, BBC and FOX, have reported that their hotel rooms have been ransacked.
Some men charged onto the roof of the Ramses Hilton Hotel where APTN maintains a satellite dish that networks, including ABC News, use to transmit their stories. They broke apart the dish and APTN technicians had to jump from the roof to another roof two floors below.
Jeffrey Schneider, senior vice president of ABC News, said, "We are assessing the security situation literally on a minute to minute basis. Our priority is to ensure the safety of all of our staff in the field."