Angry parents have lashed out at Nigerian authorities, condemning the lack of action and failure to rescue close to 200 schoolgirls abducted by suspected Boko Haram Islamists.

It has been more than two weeks since 234 girls were taken in the middle of the night from a boarding school in the Chibok area of north-eastern Borno state.

Some of them have since escaped, but it is thought about 180 are still being held captive.

Parents and supporters gathered outside government offices and pleaded for officials in Abuja to find the girls.

"May God curse every one of those who has failed to free our girls," said Enoch Mark, whose daughter and two nieces were among the students abducted from the government girls secondary school.

What is Boko Haram? Boko Haram, which means "Western education is sinful", is loosely modelled on the Taliban movement in Afghanistan.

Boko Haram, which means "Western education is sinful", is loosely modelled on the Taliban movement in Afghanistan. The group considers all who do not follow its strict ideology as infidels, whether they are Christian or Muslim.

The group considers all who do not follow its strict ideology as infidels, whether they are Christian or Muslim. It demands the adoption of Sharia law in all of Nigeria. Read more

He said the government was "showing indifference to (a) monumental disaster".

No-one has yet claimed responsibility but if Boko Haram is confirmed as being behind the kidnapping it would be one of the most shocking in the group's five-year, Islamist uprising which has claimed thousands of lives across northern and central Nigeria.

The outrage that followed the mass abduction has been compounded by disputes over figures and criticism of the military's search-and-rescue effort.

Borno officials have said that 129 girls were kidnapped when gunmen stormed the school after sundown on April 14 and forced the students - aged between 12 and 17 - onto a convoy of trucks.

Officials said 52 have since escaped.

Locals, including the school's principal, have rejected those numbers, insisting 230 students were snatched and that 187 are still being held hostage.

Mr Mark told AFP his wife had hardly slept since the attack, lying awake at night "thinking about our daughter".

Boko Haram's name translates as "Western education is forbidden", and it has repeatedly attacked schools during an insurgency aimed at creating a strict, Islamic state in mainly Muslim northern Nigeria.

The Islamists have set schools on fire, massacred students in their sleep and detonated bombs at university campus churches.

Parents take search into own hands

President Goodluck Jonathan has faced scathing criticism over the attacks and the pressure has mounted since the kidnappings.

Parents, who said they had little confidence in the military search effort, have scoured the bushlands of the remote region, pooling money to buy fuel for motorbikes and cars to conduct their own rescue effort.

Pogo Bitrus, leader of a Chibok elders group, told AFP that locals had received various tips concerning the whereabouts of the hostages, with some reports saying they had been taken across borders into Cameroon and Chad.

"The free movement of the kidnappers in huge convoys with their captives for two weeks without being traced by the military which claims to be working diligently to free the girls is unbelievable," he said.

The military deployed thousands of additional troops to the north-east last year as part of an offensive aimed at crushing Boko Haram, but security experts say Nigeria lacks the troops needed to fully cover the region.

There has been no independent confirmation of the girls being trafficked across borders and some of those who escaped said the hostages were taken to Borno's Sambisa Forest area, where Boko Haram has well-fortified camps.

Last week, the military said it had killed 40 insurgents near Sambisa Forest in an operation aimed at finding the kidnappers.

ABC/wires