Martha Mark, the mother of kidnapped school girl Monica Mark cries as she display her photo, in the family house, in Chibok, Nigeria, May 19, 2014. Sunday Alamba/AP

The head of Interpol told ABC News that he has no information to confirm or dispute the assertion earlier this week that top officials in Nigeria know the location of the 200 school girls kidnapped by Boko Haram.

"Interpol doesn't know where these 200 girls are and, if the Nigerian defense minister knows where they are, it hasn't been shared with Interpol," Ronald Noble, the secretary general of Interpol, said in an exclusive intervew with ABC News.

'This Week': The Search for Kidnapped Nigerian Girls

Noble said could understand the logic, as explained by Nigeria's Air Marshal Alex Badeh, that a rescue has not been attempted because of the danger to the girls, though he has no idea if that claim is accurate either.

Fathers of Kidnapped Nigerian Girls Ask World to Pray for Their Return

"I can tell you what everyone knows: That this terrorist group, Boko Haram, is one of the most notorious, vicious terrorist groups out there. And for them to kill these 200 girls or others very easily, very quickly, there's no doubt about it. So, if the Nigerian defense ministry does know where they are, I can certainly understand why they want to be careful before moving in to rescue these young girls."

In addition to offering technical assistance to Nigerian officials, Interpol has also blanketed the region with warnings and photos of the abducted girls to make it harder for Boko Haram to sell them, as the organization has threatened it would.

Nigeria's Plan of Action: 'War on Boko Haram'

Noble said his organization is trying to "make sure it's difficult for them (Boko Haram) to consummate the end that they want in terms of transferring these girls, selling these girls," Noble said. Distributing alerts, photos and warnings are key, he said, "so if they cross the border and are stopped by police we'll be able to identify them."