ABUJA, Nigeria (AP) -- Suspected Islamic militants have struck for a fourth time in three days in Nigeria, killing 20 people including a traditional ruler in attacks in the northeast, local government and security officials said Wednesday.
Meanwhile, the military said all but eight of more than 100 teenage students kidnapped on Tuesday are free.
The unprecedented string of attacks, which started with a massive explosion in the capital that killed at least 75 people, has many questioning the ability of Nigeria's military to contain the 5-year-old Islamic uprising. It has killed more than 1,500 people this year alone, compared to an estimated 3,600 between 2010 and 2013.
"Once again, the sophisticated methods of the bombers and insurgents, the audacity of their open attacks and the devastating stealth with which they operate ... calls into question the strategy of the Nigerian security forces and their commitment to the fight," The Guardian newspaper of Nigeria said in an editorial Wednesday.
"As Nigeria bleeds all over, a more heart-rending phenomenon is the politicization of the insurgency," the independent and authoritative newspaper said. "The ruling elite seems conscienceless enough to be exploiting the crisis, in symbols and in substance."
Just last week the emir of embattled Gwoza district had appealed to the government to "save our souls," saying his people are being attacked daily.
By Tuesday, one of his local monarchs was dead.
"They simply walked right into the palace of the monarch and shot him in his bedroom, and on their way out they also shot his guard before fleeing," said local politician Hyeldi Bwala.
Wednesday morning, gunmen attacked the village of Wala, in Gwoza district, and killed 18 people, according to a local government official and an intelligence agent. They both spoke on condition of anonymity because they are not authorized to speak to reporters.
The emir, Idrissa Timta, had indicated security forces were inadequate and said he might have to flee to neighboring Cameroon "where we may perhaps get protection."
"We in Gwoza have suffered too many attacks, killings and destruction," he said. "Our people have been forced to flee, our markets no longer operate optimally, food items, goods and wares are no longer coming in ... We want action from government so that lives can be saved."
The attacks come after Monday's explosion just miles (kilometers) from Nigeria's seat of government, timed for the busy morning rush hour to ensure maximum casualties, and Tuesday's abduction of about 100 young women taking final exams at a school, also in Gwoza.
All but eight of the young women -- they were aged between 16 and 18 -- were free by Wednesday night, military spokesman Maj. Gen. Chris Olukolade said in a statement. He gave no details.
The federal government said security forces had mounted a manhunt, and a reward of 50 million naira ($300,000) was offered Wednesday for information leading to the young women's safe return by Gov. Kashim Shettima of Borno state. He said 129 students were abducted and 14 students had managed to escape -- four who jumped from a moving open truck before dawn Tuesday, and 10 who ran away from their abductors Wednesday when they were told to cook for the insurgents.
Shettima said the principal of the boarding school told him the extremists arrived dressed in military fatigues and posing as soldiers. He said the principal believed they were taking away the students for their own safety, and it was only as they were leaving and started shooting that he realized his mistake.
The militants killed a soldier and a police officer guarding the school.
A condemnation from the 57-state Organization of Islamic Cooperation warned the abduction "tarnishes the good image of Islam" and emphasized the importance of girls' education in Islam. U.N. Secretary-General Ban Ki-moon and the organization's children's fund called for their immediate release and noted "The targeting of schools and school children is a grave violation of international humanitarian law."
The Daily Trust newspaper published a heart-warming story about the Abuja disaster, of a 10-month-old baby who was lost in the chaos of the bomb blast.
The toddler, named Goodness, was being cared for at a hospital where it was presumed her mother was among the dead. But family members found Gloria Adams, the mother, in another hospital. And then an aunt discovered baby Goodness.
Hospital officials reunited the two Wednesday, Goodness with a black eye swollen shut that doctors said they were monitoring. But Adams apparently suffered serious injuries as she is in the intensive care unit of Wuse General Hospital.
Health officials say 141 wounded victims are in 15 hospitals and clinics. The death toll is expected to rise as it does not yet include victims who were blown apart.
Meanwhile, President Goodluck Jonathan is coming under fire for traveling to northern Kano city on Tuesday for a political rally seen as campaigning ahead of elections scheduled February 2015.
"Heartless" and "insensitive" were just some of the pejoratives posted about him on social media Wednesday.
Gov. Rabi'u Kwankwaso of Kano state berated the president for "gallivanting round the country" while Nigerians are in mourning and worrying about the fate of the kidnapped students.
Jonathan's party responded that Nigeria's leader could not allow his actions to be dictated by terrorists "who seek to impose a reign of terror in our country, cow the president, dictate the tempo of government and ultimately shut down governance."
Associated Press writers Haruna Umar in Maiduguri, Nigeria, and Jon Gambrell in Cairo, Egypt, contributed to this report.
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