Nigerian military authorities know the location of the more than 200 schoolgirls that have been missing over a month, but they will not use force to rescue the girls from their Boko Haram abductors, Reuters reported.

A multinational effort has ensued to rescue the girls after Boko Haram militants kidnapped them from their school in Borno state on April 14.

Nigeria's military knows where the girls are, but officials have refused to carry out any raid-type rescue effort out of fear of retaliation from the militants.

"The good news for the parents of the girls is that we know where they are, but we cannot tell you," Chief of Defense Staff Air Marshal Alex Badeh told that state run news agency, according to Reuters. "But where they are held, can we go there with force? We can't kill our girls in the name of trying to get them back."

The Nigerian government also pulled out of a deal with the Islamist militants at the last minute, the BBC reported on Monday. The militants had agreed to release some of the girls in exchange for the government's freeing of Boko Haram prisoners. It is not clear why the government called off the deal, the BBC reported.

The government has maintained it will not negotiate with Boko Haram, despite increased international pressure and local protests against the government's lack of action to return the girls.

"This government cannot negotiate with criminals and...will not exchange people for criminals," Senate President David Mark said according to Reuters. "A criminal will be treated like a criminal."

The hashtag BringBackOurGirls is trending on Twitter, with noted people from Michelle Obama to Emma Watson posting pictures of them holding sings with the plea.

Boko Haram has recently increased its attacks on civilians ever since it began its campaign to form an Islamic state in 2009.

At least 470 civilians alone have been killed since the girls were abducted from their boarding school in the village of Chibok, Reuters reported.

Boko Haram translates to "Western education is forbidden."