Khartoum - Intensified bombing in Sudan's war-torn South Kordofan may be part of an attempt to starve the population, Amnesty International said on Wednesday.
The air raids in recent weeks are "unprecedented in their scale and impact," the London-based watchdog said, citing human rights monitors.
In the last week of May, 59 bombs fell in and around Kauda, a stronghold of the Sudan People's Liberation Movement-North (SPLM-N), Amnesty said in a briefing paper.
Between 15 and 22 May, Sudan's air force dropped around 200 bombs over the agricultural area of Tangal in Umm Durain district, severely disrupting the planting season, it said.
"The intensification of bombings reported in the last two months may indicate that SAF (Sudanese Armed Forces) are intentionally attempting to disrupt planting season," Amnesty said, adding there has been a pattern of increased attacks during key farming months since the war began three years ago.
"The combined effect of the interference with planting and harvesting in Southern Kordofan with the refusal by the Sudanese government to allow humanitarian assistance may demonstrate a deliberate use of starvation as a method of warfare, which constitutes a war crime."
Amnesty said it has also received from human rights monitors "worrying reports" that the Rapid Support Forces (RSF) have burned and destroyed properties and civilian objects such as water holes and grain stores.
Peace and security
The paramilitary RSF have denied accusations that they attacked villages in Sudan's Darfur region.
"I think that, on the contrary, such accusations should be directed to the rebels," Rabbie Abdelatti Ebaid, a senior official in Sudan's ruling National Congress Party, told AFP.
"It is the responsibility of our government to protect civilians," while aiming to establish peace and security, he said.
Sudan tightly restricted the movement of aid agencies in South Kordofan after fighting with SPLM-N erupted in June 2011.
Since that year, humanitarians have had no access into SPLM-N areas from within Sudan.
At least 30-40% of displaced people and poor households in SPLM-N-controlled areas would face "emergency food insecurity", the Famine Early Warning Systems Network forecast in an April report.
The Network was created by the United States Agency for International Development.
Like the 11-year conflict in Darfur, the South Kordofan war has been fuelled by complaints among non-Arab groups of neglect and discrimination by the Arab-dominated regime.