After raiding four camps in Boko Haram's forest stronghold in northeast Nigeria, the Nigerian army is working to identify nearly 300 women — including 200 schoolgirls — who were rescued in the operation.

Though an army spokesman initially stated that none of the women were the missing Chibok schoolgirls kidnapped more than a year ago by the militant group, the military now says their exact origins are still unknown. The women have reportedly been evacuated from the Sambisa Forest region where they were being held, and will undergo screening to determine how they ended up in Boko Haram captivity.

"Now they are excited about their freedom," Nigerian army Col. Sani Usman told Reuters. "Tomorrow there will be screenings to determine whether they are Boko Haram wives, whether they are from Chibok, how long they have been in the camps, and if they have children."

Human rights groups estimate that Boko Haram has kidnapped some 2,000 women since the Chibok attack on April 14, 2014. The latest development comes weeks after the one-year anniversary of the Chibok kidnappings, which sparked domestic uproar, international condemnation, and the Twitter hashtag campaign #BringBackOurGirls. Though 57 of the Chibok girls managed to escape, 219 remain missing.

According to unnamed Nigerian military sources cited by the Associated Press, Boko Haram used some of the women rescued Tuesday as "armed human shields," who fired on the Nigerian soldiers while acting as a first line of defense for the militants.

Gen. Chris Olukolade told the BBC that security forces were able to locate the hostages and the camps using military intelligence. Nigeria's military initiated its campaign in Sambisa — an area where some believe the Chibok girls may be located — in March, largely waging air raids over the region.

While Nigerian forces — backed by troops from neighboring Chad, Niger, and Cameroon — have pushed back against Boko Haram, the militant group has continued to make advances in the country while further aligning itself with the Islamic State. In images released last week on social media, the Islamic State praised Boko Haram and referred to them as their "West Africa Province." The Islamic State now has a significant presence in Libya, but the group is still primarily based in Syria and Iraq, raising doubts about the level of coordination with Boko Haram.

Across the border in Niger, local troops took a hit against Boko Haram in violent clashes over the weekend. The country's ministry of defense reported that 46 troops died in a battle to retake Lake Chad's Karamga Island. More than 150 militants were reportedly killed in the fighting.

Niger's forces ultimately secured control over the territory, but Interior Minister Hassoumi Massaoudou said "the village has been completely devastated." The government announced a three-day state of mourning for 28 civilians killed in the crossfire.

The recent operation in Lake Chad is the latest in a multi-national offensive to thwart Boko Haram. The group has displaced 1.5 million people and killed an estimated 5,500 others over the last six years. Niger's army chief Seyni Garba told a national television audience that the recent bloodbath would not weigh on the continued mission against the militant group.

"This act by Boko Haram should not rattle our determination," Garba said.