By Fred Pleitgen and Mohamed Fadel Fahmy, CNN

(CNN) - Hundreds of African refugees have been released from captivity in the Sinai Peninsula and allowed to cross from Egypt into Israel, shortly after a CNN report detailed the horrendous conditions the migrants face.

The report, "Death in the Desert," which was first published online in early November and broadcast on CNN International on November 5, showed evidence that African refugees, mostly from Sudan and Eritrea, were being held captive by Bedouin human traffickers in Sinai, who try to extort massive sums of money from the refugees’ families for their release.

While in captivity the refugees are enslaved, many of the women raped and some even killed. The CNN crew even found evidence that some victims had organs extracted, a practice known as organ harvesting, and were later found dead in the desert.

Shortly after the report, more than 600 African refugees were released in Sinai, says Hamdi al Azzazy, an activist for the New Generation Foundation for Human Rights who has worked for years in the region, fighting to improve the plight of the African refugees.

His account was backed up by a press release from the EveryOne Group, an Italian non-governmental organization, which has also been raising public awareness about the refugees.

It said that after the CNN report, "many chief-traffickers were afraid of being pursued by the authorities and on Wednesday, November 9th, 2011 decided to release most of the groups of refugees they were holding prisoner."

The Sinai Desert is a vast and lawless area where the Egyptian state has virtually no presence and it is nearly impossible to fully verify the accounts.

CNN has contacted a chief of the Sawarka Bedouin tribe. Some rogue members of this tribe have been implicated in the imprisonment of African refugees and in the organ harvesting scheme.

The chief, who has asked not to be named said: "I heard the Sawarka's members involved in this dirty business released more than 600 Africans without them having to pay the ransoms and sent them to the Israeli border due to pressure from the intelligence service, including hundreds who were freed from the house of the assassinated dealer in Nekhel. He has been selling their organs and they found lots of weapons."

EveryOne Group says the alleged trafficker in people and human organs - known as "The Sultan" - was killed in a shootout with some Bedouins of another tribe, who were attempting to free a group of Eritrean refugees.

An Egyptian general, who asked not to be named, told CNN that Egypt's national security agencies were "tracking the rings of organized criminals involved in human trafficking but remain perplexed regarding who exactly is harvesting the organs and where they have been sold."

He said the investigation included "both the Egyptian intelligence and the National Security apparatus because it involves several countries and is not just an internal issue."

The UNHCR, which attempts to keep track of refugees crossing from Egypt to Israel, has confirmed that about 650 refugees have recently crossed the border.

Peter Deck, the Senior Protection Officer for the UNHCR in Tel Aviv, said it was impossible to tell why so many refugees were suddenly crossing the border or what role CNN's Freedom Project program may have played in people getting released from Bedouin detention camps, but he added that November was on track to becoming a record for the most crossings by refugees from Egypt to Israel.

He said that aside from the sheer numbers, the conditions had also changed. Many of those who crossed into Israel had stayed in Sinai for about a week, whereas usually the African refugees are held in Bedouin camps for months, and that most had paid substantially less to be allowed to pass then is normally the case.

Another change he noted was: "We didn’t have any refugees complain of severe physical abuse or violence… something seems to be different in those Bedouin camps."

The American University in Cairo is hosting a conference this weekend at which a delegation from The International Criminal Court will address human trafficking through Africa, Sinai, and Israel.

CNN's Tim Lister contributed to this report.