By Olivier Knox

Former British Prime Minister Gordon Brown told Yahoo News on Tuesday that the world must band together 100 days after the mass abduction of Nigeria schoolgirls to send the message that “we will not forget” the more than 200 children still in the clutches of extremists.

Brown, now a United Nations special envoy for global education, told Yahoo Global News Anchor Katie Couric that he hoped the recent arrival of helicopters, night-vision equipment and other gear to aid in the search for the girls would yield a breakthrough.

“I hope that in the next few weeks we can see more positive results than we’ve seen in the last hundred days,” Brown said. “This is every parent’s nightmare.”

The kidnapping, carried out by the Boko Haram group, drew global condemnation, notably through widespread use of the #BringBackOurGirls hashtag on Twitter. The White House criticized the government of Nigerian President Goodluck Jonathan for its sluggish response to the crisis and initial reluctance to accept U.S. help.

An international mobilization, including a special team to help coordinate search efforts and reconnaissance flights, has failed to date to rescue the girls and return them to their families. Equipment and other help have come in from Eastern Europe, China, the United States, Britain, France, and Israel. Officials fear that the young women have been separated into smaller groups, with some scattered elsewhere in Nigeria and others taken over the borders into Chad, Cameroon and Niger.

Asked why they had not yet been rescued, Brown replied: “Because they’re being held by a terrorist group that is intent on causing the maximum damage.”

“And while I think they’ve been located, at least some of them have been located, they have been split up as a group, and therefore it is very difficult to rescue one group without putting at risk the others,” said Brown.

“It’s possible that some are in Cameroon. It’s possible that some are in Niger. It’s possible that some are in other countries now, and it’s also possible that the long-term plan of Boko Haram is to disperse some of them across the whole of Africa,” Brown said.

The former prime minister urged people around the world to show public support for the families and for girls’ education.

“We must show, in the international community, a hundred days after they’ve been taken into captivity, we will not forget, we will always remember the plight that they are facing and the dangers they are undergoing, and we will keep the torch for these girls alive and lit so that the whole world knows that we must do everything in our power to rescue them,” he said.

“The families will see that they are not without support and they should not lose hope, because the efforts are intensifying to bring back the girls,” Brown said. “We are not forgetting them. We’re trying to do everything we can to bring them back.”

Asked about the downing of Malaysia Airlines Flight 17, Brown branded it “a terrorist act” and called for a investigation under U.N. auspices. And he echoed Western suspicions that the passenger jet was shot down by Moscow-backed separatists in eastern Ukraine.

Brown also recalled his “very difficult dealings” with Russian President Vladimir Putin – notably over the assassination of Alexander Litvinenko, a former KGB spy, in London in 2006. Russia has refused to deport the lead suspect, a Russian also thought to have ties to the KGB.

“As you know, there was a murder that took place in London and it was traced back to people in Russia, and from that moment, relations between myself and President Putin were very difficult,” he said.

When it comes to the downed airliner, “we’ve got to remember that any government or any group of leaders in any country that are either directly or indirectly responsible for an act which caused a huge amount of disturbance or damage or indeed the loss of lives, they’ve got to be held accountable in this modern international community,” he said.

Asked about the fighting between Israel and Hamas militants in the Gaza Strip, Brown called for a ceasefire “as quickly as possible,” followed by renewed efforts to forge “a more lasting peace” based on the creation of a Palestinian state living at peace with Israel.

Brown also repeated his opposition to Scottish independence and predicted that voters will reject severing ties with the rest of the United Kingdom in a September 18 referendum.