KANO, Nigeria (AFP) - US President Barack Obama on Tuesday described the kidnapping of more than 220 schoolgirls by Islamists in Nigeria as "heartbreaking" and "outrageous" as Washington deployed military experts in the hunt for the children.
Mr Obama urged global action against Boko Haram and confirmed Nigerian leaders had accepted an offer to deploy US personnel there, soon after residents said the extremist group had seized eight more girls, aged between 12 and 15, again in the embattled northeast.
The first group of girls were taken three weeks ago, and concerns have been mounting about their fate after Boko Haram chief Abubakar Shekau claimed responsibility, saying his group was holding the schoolgirls as "slaves" and threatening to "sell them in the market".
Speaking to US broadcaster ABC, Mr Obama said: "It's a heartbreaking situation, outrageous situation."
"This may be the event that helps to mobilise the entire international community to finally do something against this horrendous organisation that's perpetrated such a terrible crime," he added.
The team sent to Nigeria consists of "military, law enforcement, and other agencies", Mr Obama said, and will work to "identify where in fact these girls might be and provide them help".
He denounced Boko Haram as "one of the worst regional or local terrorist organisations".
US officials have voiced fears that the more than 220 girls, aged between 16 and 18, have already been smuggled into neighbouring countries, such as Chad and Cameroon. The governments of both denied the girls were in their countries.
Their fate has sparked global outrage and may constitute a crime against humanity according to the UN.
- 'Heinous people' -
Shekau said his extreme Islamist group was holding the schoolgirls abducted on April 14 in the northeastern town of Chibok as "slaves" and threatened to "sell them in the market", in a video obtained by AFP on Monday.
Parents of those taken said Shekau's video had made an already horrifying situation even worse.
"All along, we have been imagining what could happen to our daughters in the hands of these heinous people," one mother, Lawal Zanna, told AFP by phone from Chibok.
The latest kidnappings also took place in Borno state, a stronghold of the Islamist group.
Abdullahi Sani, a resident of Warabe, said gunmen had moved "door to door, looking for girls" late on Sunday.
"They forcefully took away eight girls between the ages of 12 and 15," he said, in an account confirmed by other witnesses.
He said the attackers did not kill anyone, which was "surprising", and suggested that abducting girls was the motive for the attack.
Another Warabe resident, Peter Gombo, told AFP that the military and police had not yet deployed to the area.
"We have no security here. If the gunmen decide to pick our own girls, nobody can stop them."
- 'Too much to bear' -
Though initially slow to emerge, global outrage has flared over the mass abduction in Chibok, where Boko Haram stormed their school and loaded the girls at gunpoint onto trucks.
Several managed to escape but over 220 girls are still being held, according to police.
British Foreign Secretary William Hague called the kidnappings "disgusting" while Angelina Jolie, speaking in Paris, condemned the Chibok abductions as "unthinkable cruelty and evil".
Egypt's prestigious Islamic institute Al-Azhar, which runs the main Sunni Islamic university in the region, said harming the girls "completely contradicts the teachings of Islam".
Since the attack, parents have criticised the military's rescue mission, saying there had been a lack of urgency from the outset.
Enoch Mark, an outspoken critic of the authorities since his daughter was kidnapped in Chibok, said "the government should find our girls or seek international assistance if it cannot".
"Boko Haram are not spirits or extra-terrestrial creatures that cannot be tracked and subdued," he told AFP by phone. "The agony and trauma are becoming too much for us parents to bear."
The military said it had launched a major search operation, including in the Sambisa Forest area of Borno where Boko Haram has well-fortified camps.
- Pressure on president -
As well as mounting pressure over the kidnappings, Nigerian President Goodluck Jonathan must also contend with a spate of terrorist attacks, including a car bomb that ripped through a crowded bus station on the outskirts of Abuja just a few hours before the mass abduction leaving 75 dead - the deadliest attack yet in the capital.
A copycat bombing at the same station killed 19 people on May 1.
Mr Jonathan had hoped that a World Economic Forum summit which opens in Abuja on Wednesday would highlight Nigeria's economic progress and underline its recent emergence as Africa's biggest economy.
But it is Boko Haram's extreme violence that has dominated headlines, with many questioning whether Nigeria has the capacity to contain the insurgents who have killed thousands since 2009, and at least 1,500 this year alone.
The group, which says it wants to create an Islamic state in mainly Muslim northern Nigeria, has vowed to carry out further attacks across the country, including in the Niger Delta, home to Africa's largest oil industry.