Boko haram has released a video showing the girls wearing black hijabs in an unspecified location, stating their names, that they were taken from Chibok and the date of the recording -- December 25, 2015, the broadcaster said.

Two of the three mothers of the 219 schoolgirls still missing since the mass abduction on April 14, 2014 recognised their daughters on the video but another broke down as hers was not there . all three, however, identified all the girls, as did a classmate, who was at home on the day of the kidnapping.

The video is the first concrete indication that at least some the girls are still alive since a previous video released publicly by Boko Haram in May 2014.Then, about 100 of the teenagers were shown in Islamic dress, reciting passages from the Koran after Boko Haram leader Abubakar Shekau said they had converted to Islam .

Nigerians information minister Lai Mohammed told CNN the girls in the video appeared "under no stress whatsoever" and there had been "little transformation in their physical appearance".But he declined to comment directly on the state of talks with Boko Haram, which has previously said it would release the girls only in exchange for captured fighters in Nigerian prisons."There are ongoing talks. We cannot ignore leads but of course many of these investigations cannot be disclosed openly because it could also endanger the negotiations," the minister added.

- Two year anniversary -

Nnamdi Obasi and Ayo Obe, of the International Crisis Group, described the anniversary was an opportunity to address the conflict's effect on children as more areas are freed from Boko Haram's control.

"The currently haphazard approach to the rehabilitation of rescued captives has left most of them psychologically, socially and culturally vulnerable," they added in an article published on blog.crisisgroup.org.

Human Rights Watch said this week some 952,000 of the 2.6 million people displaced by the violence were children, who had been "robbed" of their right to education by attacks on schools.UNICEF said separately there had been a sharp rise in the use of abducted children as human bombs. Three-quarters of the child bombers in attacks from January 2014 to February2016 were girls.