Boko Haram has abandoned so many hundreds of kidnapped women and girls recently that Nigerian officials tasked with bringing them back into society on Sunday said they were looking to open a second rehabilitation camp, a nod to how fast the tide of abductions has reversed.

In the past few weeks, as troops from Nigeria and surrounding countries have punched deep into Boko Haram territory, soldiers said they have rescued about 1,000 women and girls, hostages the Islamist insurgency left behind.

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