Thirty more of the 276 Nigerian schoolgirls abducted by Boko Haram militants in April have reportedly escaped from their captors, according to local sources."The militants had gone to attack some villages in the Madagali local government area [of Adamawa State], which borders the Sambisa Forest in Borno State, when the girls fled because they had been left without much guard," Abdul Jalal, a member of a local vigilante group, told Anadolu Agency on Wednesday."They [the escaped girls] are currently receiving treatment in a hospital in Madagali," he said.Madagali is located some 10km from the Sambisa Forest, a known Boko Haram stronghold in Nigeria's northeastern region.On April 14, Boko Haram militants abducted 276 schoolgirls in Borno's town of Chibok, according to official figures.Boko Haram kingpin Abubakar Shekau later claimed responsibility for the abductions, offering to trade the girls for some of his fighters held by the authorities."The girls said they were being kept in a building right inside Sambisa Forest," Abdul Jalal told AA.The escaped girls, he said, had said that more than 30 of them had tried to escape but that some had been shot down by their captors."It is not clear if those who were shot died or not," said the local vigilante.A security official in Chibok confirmed the girls' escape.Neither the local Borno government nor the military has responded to AA's enquiries about the reported escape.If confirmed, it would bring to 87 the total number of girls to have escaped from Boko Haram to date, leaving 189 still in captivity.Boko Haram, which means "Western education is forbidden" in Nigeria's local Hausa language, first emerged in the early 2000s preaching against government misrule and corruption.The group later became violent, however, after the death of its leader in 2009 while in police custody.In the five years since, the shadowy sect has been blamed for numerous attacks-on places of worship and government institutions-and thousands of deaths.