Tensions remain high in the central Nigerian city of Jos after gunfire erupted in an area near villages where hundreds were killed two days ago.

The automatic gunfire, which went on for about three minutes on Tuesday, sent more than a hundred villagers - many women and children - fleeing for cover.

A police officer in Jos, speaking on condition of anonymity, told the Associated Press news agency that soldiers opened fire to scare away a crowd that had gathered in the street because of a suspicious truck in their neighbourhood.

Curfew remains

A heavy security presence and a curfew remain in Jos and police say they have arrested more than 90 people in connection with Sunday's attacks in which three mostly Christian villages near Jos were attacked by Muslim Hausa-Fulani herders, leaving more than 500 people dead.

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Some described the violence as a reprisal attack for the more than 400 people killed in January clashes between Christians and Muslims.

Al Jazeera's Yvonne Ndege, reporting from Jos, said that while many people would view Sunday's violence in a religious context, people she had spoken to said the violence was about indigenous groups, who are mainly Christian, and migrants and settlers, mainly from the Hausa-speaking Muslim north, competing for access to resources.

Robin Waudo, a spokesman for the International Committee of the Red Cross (ICRC), told Al Jazeera that officials from the ICRC and the Nigerian Red Cross who went to Jos on Tuesday had discovered that there was "a lot of humanitarian challenges".

"What has been found is that most of the houses were either razed down or destroyed, displacing nearly all the inhabitants - we're talking [about] between 4,000 and 5,000 - so this is the big challenge because they need to be provided with shelter, food, water and clothing," he said.

"It's difficult to predict more violence and we cannot speculate, but we've to respond to the present situation that faces us." 

Goodluck Jonathan, Nigeria's acting president, sacked Sarki Muktar, his national security adviser, on Tuesday and vowed to lock down the borders of Plateau State, where villages are located, to stop weapons and potential fighters from infiltrating the region.

Jonah Jang, the governor of Plateau State, however, criticised the central government on Tuesday, telling Al Jazeera that he had warned the army of suspicious people with weapons near the villages several hours before the attack, but was ignored.

Source: Al Jazeera and agencies