Boko Haram leader mocks campaign to free kidnapped girls

Boko Haram mocks attempts to rescue kidnapped... 02:14

JOHANNESBURG - Three months after the kidnapping of hundreds of Nigerian schoolgirls, the Islamic militant leader behind the abduction surfaced in a video Sunday with a defiant and dismissive message.

For 90 days the families of the more than 200 girls had hoped for good news. Instead, their hopes were met with scorn in a new video from Boko Haram leader Abubaker Shekau, who mocks the "Bring Back Our Girls" campaign.

Boko Haram warns of more kidnappings 02:45

"'Bring Back Our Girls.' Ooooh! Bring back our army," he says on the video, jeering at the Nigerian military.

The social media campaign #BringBackOurGirls quickly drew worldwide attention to the plight of the Chibok schoolgirls. But just as quickly, it faded from the global spotlight. And in that time Boko Haram has stepped up its terror campaign. In the new video, Shekau claims responsibility for a June bomb blast in the capital, Abuja, which left 21 dead.

Nigerian schoolgirls appear anxious in Boko H... 02:28

While attempts to rescue the girls appear to have stalled over past weeks, sources close to the negotiations tell CBS News that back-door channels remain open. They even believe there could be action within days. But they warn against raising expectation as they say they've been close to a breakthrough on three separate occasions - only to have the rescue efforts aborted at the 11th hour.

There was a measure of comfort for the Chibok parents on Sunday when they were visited by Malala Yousefzai, the young Pakistani girl shot by the Taliban for also having the audacity to seek an education.

Pakistani schoolgirl activist Malala Yousafzai speaks during a meeting with the leaders of the #BringBackOurGirls Abuja campaign group, in Abuja July 13, 2014. AFOLABI SOTUNDE, REUTERS

"You are really brave parents, really brave parents who have taken the step to speak up for their daughters and to speak up for the right of education and I'm hopeful that the government would listen to your voice," she said.

So far the Nigerian government has appeared impotent in the face of the increasingly brazen Boko Haram attacks. Sources tell CBS News they have all but ruled out a military rescue as it could further endanger the lives of the girls.

This means there are few options left for a government facing strong criticism from its own people over their failure to bring the Chibok girls safely home.