By Alexis Akwagyiram
KADUNA, Nigeria Jan 13 (Reuters) - Hundreds of people have died in a surge of ethnically-charged violence in Nigeria's divided heartlands, officials said, piling pressure on a government already facing Islamist militants in its northeast and rebels in its oil-rich south.
Locals in remote villages in Kaduna state told Reuters Muslim herders had clashed with largely Christian farmers repeatedly in recent weeks, in the worst outbreak of killings in the region since riots killed 800 after elections in 2011.
The fighting triggered by competition over scarce resources has come at a particularly sensitive time for Kaduna city, which is about to become the main air hub in central and northern Nigeria, after the capital Abuja's airport closes temporarily for runway repairs in March.
Farmer Ibrahim Sabo said cattle herders armed with assault rifles raided his village Kalangai in southern Kaduna in November, forcing him and his family to hide in surrounding fields.
"We left everything we harvested and they took our cattle. We have been running ever since," said the 75-year-old in Kakura village where he took refuge.
The violence has focused attention on President Muhammadu Buhari, a former military ruler who vowed to restore order in Africa's most populous nation when he came to power in May 2015.
He held a five-hour session with senior security and army officials in Abuja on Thursday on how to tackle the unrest.
Security agencies are already deploying extra forces to secure Kaduna's airport and its highway to Abuja, a route often targeted by kidnappers.
That all comes on top of an insurgency by Boko Haram Islamists in the northeast, beaten back last year by a military coalition of neighbouring nations, but showing signs of a resurgence with a recent step-up in bombings.
Militants in the southern Niger Delta oil hub have said they are ready to resume pipeline attacks, and there have also been clashes between Shi'ite and Sunni Muslims in Kaduna state.
Locals say the Kaduna violence grew out of festering disputes over territory in October and November, then escalated sharply, exacerbated by north-south, Muslim-Christian tensions in a patchwork nation.
Details of attacks and precise figures are hard to come by in the remote territory.
The national disaster agency NEMA said on Friday it had recorded a total of 204 deaths since October in Kafanchan and Chikun, two of the four municipal districts worst hit by the violence, with no details from the others.
Christian leaders released a statement late December saying 808 people had died - an estimate dismissed by Kaduna state police commissioner Agyole Abeh who did not give his own figure.
The authorities had already sent in reinforcements - 10 units, each with 63 police officers, using 20 armoured cars, he added.
Community group, the Miyetti Allah Cattle Breeders Association of Nigeria, said herdsmen had been "unjustifiably accused and maligned" in the area and had also come under attack, prompting a cycle of revenge.
There were few signs of the promised police or army reinforcements outside the centre of Kaduna city.
Tarmac roads gave way to red soil dirt tracks leading to Kakura, on the edge of the territory that has seen the worst fighting.
Another farmer, Yusuf Dogo, said dozens of armed herdsmen burned houses in his village of Pasakori in three quick raids, forcing 700 people to flee in October.
"They ran through our village and started shooting randomly," he said. "Later, they brought their cattle and they ate everything."
(Additional reporting by Garba Muhammad in Kaduna and Felix Onuah in Abuja; Editing by Ulf Laessing and Andrew Heavens)