The Islamist militant group Boko Haram in Nigeria has threatened to “sell” the hundreds of schoolgirls it abducted three weeks ago.

Militant leader Abubakar Shekau sent a video obtained by the AFP news agency, in which he said for the first time that his group had taken the girls.

About 230 girls are still believed to be missing, prompting widespread criticism of the Nigerian government.

The Boko Haram insurgency has left thousands dead since 2009.

The girls were taken from their school in Chibok, in the northern state of Borno, on the night of April 14.

The Islamist militant group Boko Haram in Nigeria has threatened to “sell” the hundreds of schoolgirls it abducted three weeks ago

Boko Haram, which means “Western education is forbidden” has staged numerous previous attacks on educational institutions in northern Nigeria.

In the video, Abubakar Shekau said the girls should not have been in school in the first place, but rather should get married.

“God instructed me to sell them, they are his properties and I will carry out his instructions,” he said.

However, the Boko Haram leader did not state the number of girls abducted, nor where they were taken or are now.

Assurances from President Goodluck Jonathan have done little to convince Nigerians of the government’s commitment to freeing the girls, says our correspondent.

Meanwhile, a woman who helped organize protests over the abduction was detained and later released.

Naomi Mutah was taken to a police station after a meeting called by First Lady Patience Jonathan.

Patience Jonathan reportedly felt slighted that the girls’ mothers had sent Naomi Mutah to the meeting instead of going themselves.

Analysts say Patience Jonathan is a politically powerful figure in Nigeria.

Naomi Mutah, a representative of the Chibok community, organized a protest last week outside parliament in Abuja.

The protesters, and many Nigerians, feel the government has not done enough to find the abductees.

The girls were in their final year of school, most of them aged 16 to 18.

Pogo Bitrus, another Chibok leader, said he had been to the Asokoro police station where Naomi Mutah is reported to have been taken but could find no written record of her being there.

He described the detention as “unfortunate” and “insensitive”, adding that he hoped Patience Jonathan would soon “realize her mistake”.

Pogo Bitrus noted that Patience Jonathan has no constitutional power to order arrests.

The AP news agency quotes another community leader, Saratu Angus Ndirpaya, as saying that Patience Jonathan accused the activists of fabricating the abductions to give the government a bad name.

She also said the First Lady accused them of supporting Boko Haram.

In a TV broadcast on Sunday, his first comment on the abductions, President Goodluck Jonathan said he did not know where the girls were but everything was being done to find them.

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