Nigerian President Goodluck Jonathan on Sunday ordered top security chiefs and officials to secure the safe release of 223 schoolgirls abducted three weeks ago by suspected Islamists, his spokesman said.

Gunmen believed to be Boko Haram Islamists stormed the girls' boarding school on April 14, forcing them from their dormitories onto trucks and driving them into the bush.

Desperate parents of the more than 200 abducted schoolgirls in Nigeria called on Saturday for authorities there to bring in foreign help to secure their release.

Frustrated by the lack of progress so far in trying to free their daughters, the parents called on Nigerian authorities to use support from other countries.

U.S. Secretary of State John Kerry on Saturday vowed that Washington will do "everything possible" to help Nigeria deal with Boko Haram militants, following the kidnapping of scores of schoolgirls.

"Let me be clear. The kidnapping of hundreds of children by Boko Haram is an unconscionable crime," Kerry said in a policy speech in the Ethiopian capital Addis Ababa.

A car bombing at a bus station on the outskirts of Nigeria’s capital killed at least 18 people and injured 80, an official said Friday, just weeks after Boko Haram Islamists attacked the same spot.

The explosion rocked the crowded Nyanya bus terminal just a few kilometers from central Abuja at roughly 8:00 pm (1900 GMT) on Thursday, 50 meters from the site of an April 14 bombing that killed at least 75 people.

Nigerian protesters marched on parliament Wednesday to demand the government and military do more to rescue scores of schoolgirls kidnapped by Boko Haram Islamists more than two weeks ago. 

Dubbed "a million woman march" and promoted on Twitter under #BringBackOurGirls, the protest was not expected to draw a massive crowd and turn-out was hindered by heavy rain in the capital Abuja. 

Nigerian parents lashed out on Tuesday at the government's failure to rescue scores of schoolgirls kidnapped by Boko Haram Islamists two weeks ago, as families agonized over the uncertain fate of the hostages.

"May God curse every one of those who has failed to free our girls," said Enoch Mark, whose daughter and two nieces were among over 100 students abducted from the Government Girls Secondary School in the Chibok area of northeastern Borno state. 

Clashes between rival tribes have left at least 34 people dead with homes and barns torched in a village in central Nigeria, the state government told Agence France Presse on Sunday.

The violence erupted Saturday when a militia from the Eggon tribe attacked the Gwandara village of Egan following a dispute over farmland, said Nasarawa state spokesman Sani Musa Mairiga.

More than 40 insurgents and four soldiers died in clashes between Nigerian troops and Islamists near the scene where scores of abducted girls are believed to be held in the north of the country, the military said Friday.

"The capture of a number of terrorists believed to be the ringleaders of those operating around Alagarmo sparked off a major fight on the outskirts of Bulanbuli, Borno State last night," defense spokesman Major General Chris Olukolade said in a statement.

The Judicial Police has arrested a Nigerian member of a so-called “black dollar scam” gang that has fraudulently obtained money from a number of Lebanese victims.

“Following intensive investigations in the Bir al-Abed area, the Dahieh Judicial Police department managed to arrest on Tuesday night a member of a Nigerian gang operating outside Lebanon,” the Internal Security Forces said in a statement issued on Thursday.

Gunmen killed at least 17 people in an attack on a village in eastern Nigeria where scores of people have died in ethnic violence in recent weeks, police said Wednesday.

Residents of the predominantly Christian village in Taraba state put the death toll from Tuesday's attack at 35 and said another 15 were still missing.