US team arrives in Nigeria to help in hostage search: embassy

US experts have arrived in Nigeria to help rescue more than 200 schoolgirls being held hostage by Boko Haram Islamists, an embassy spokeswoman said today.

"They are here...The team is on the ground," Rhonda Ferguson-Augustus told AFP, without specifying the precise make-up of the group.

US officials have previously said Washington would send military personnel as well as specialists from the Justice Department and the FBI.

Britain, France and China have also offered varying levels of assistance, including planning and coordination specialists as well intelligence and satellite imagery.

Speaking at the World Economic Forum in Nigeria's capital Abuja today, President Goodluck Jonathan restated that his country was "totally committed to getting these girls back."

Nigeria's initial response to the April 14 mass abduction in the northeastern town of Chibok was widely criticised, and for several days Jonathan said very little about the shocking attack.

But this week outrage over the girls plight has spread across the world, helped by a growing social media campaign with the hashtag #BringBackOurGirls.

The campaign has drawn support from celebrities and prominent personalities ranging from US First Lady Michelle Obama to the actress Angelina Jolie.

A chilling video by Boko Haram's leader Abubakar Shekau, in which the wanted Islamist leader threatened to sell the hostages "in the market", has also raised awareness about the attack.

National Security Adviser Sambo Dasuki, top army brass and police chief Mohammed Abubakar made a joint visit yesterday to Chibok, which falls in Nigeria's restive and deeply impoverished northeast, where Boko Haram was founded more than a decade ago.