The tribal differences are now becoming evident in Libya, he said.
"The country has never been fully unified as a national entity. It's a country of tribes with some less loyal to Gadhafi. What's happening in the eastern part of the country now has historically been a problem of consolidating power."
The uprising began in the eastern part of Libya, including the city of Benghazi. With communications to Libya cut, it has been difficult to gauge a clear sense of what's happening on the ground. But residents describe a virtually split country, with the eastern half under police and civilian control, whileTripoli and parts of the west still facing what some say is a "bloodbath" at the hands of Gadhafi's mercenaries.
In Benghazi, the doctor ABC News reached by phone described a more calm scene, saying police and military forces have joined civilians to take over the leadership of the country.
"People [in Benghazi are] very happy now because Gadhafi is gone from Benghazi. He no more control the area," the doctor said. "Now everything is secure. No more blood, but in Tripoli it's a disaster."
In Tripoli, witnesses describe a chaotic scene, with helicopters attacking protesters as Gadhafi supporters in Land Cruisers fire at people at will.
"Tripoli is burning," Libya's ambassador to the United States, Ali Suleiman Aujali, said on "Good Morning America" today. "The people are being killed in a brutal way. The people are armless."
Even residents holed up in their homes aren't safe, eyewitnesses say.
"It's really bad out there. Everyone's getting killed. I mean, it's getting worse and worse right now," said one Libyan woman based in Tripoli. "They're just killing people in the streets."