While the world’s attention has focused on the horror unleashed against the Rohingya population in Myanmar’s West, an old war in the country’s North has taken on a new ferocity, forcing thousands to leave their homes and farms and flee for their lives.

Since early April, 5,000 people in northern Kachin state have fled renewed fighting between the Myanmar military, known locally as the Tatmadaw, and ethnic Kachin rebels, according to the U.N. Up to 2,000 people remain trapped in conflict-stricken areas with little access to food and clean water.

Many who have fled are packed into overcrowded churches, squatting with host communities, or squeezing into existing displacement camps, but resources are stretched and food and water supplies are dwindling.

“The Tatmadaw came and there was lot of fighting. It wasn’t safe, so we fled,” says La Seng, a Kachin man from Bum Nan Yan village in Injayang township. La Seng, whose name has been changed for security reasons, fled to a church on the outskirts of the state capital Myitkyina. He’s crammed into the compound with 1,106 others currently seeking shelter there, but more displaced people are expected to arrive as the fighting continues. “There was fighting in the village: airstrikes the first time, then big weapons, then smaller guns,” he says though an interpreter.

Read More: Inside the Kachin War Against Burma

In what is one of the world’s longest civil wars, the Kachin Independence Army (KIA), an ethnic militia of about 10,000, has been fighting the Myanmar military for political autonomy and federal rights for more than 60 years. Since a 17-year ceasefire broke down in 2011, hundreds of civilians have been killed and more than 100,000 displaced. Atrocities against civilians, such as torture and rape, have been reportedly perpetrated on both sides.

While sporadic fighting over resources and territory is common in the mountainous state, aid groups are concerned that this current escalation is more widespread than before, with conflict reaching five townships near the border with China including Tanai, Hpakant, Injingyang, Sumprabum and Waingmaw. Villagers and aid workers say that since April 11, the Myanmar military has conducted aerial bombing and mortar campaigns, causing civilian casualties and mass displacement. Many people displaced in previous bouts of fighting have been forced to flee yet again.

“Escalation of military operations and the use of airstrikes and heavy artillery in close proximity to [displacement] camps and populated areas have increased civilian casualties, injuries, and displacement and intensified fear and anxiety for [displaced people] and civilian populations,” Gum Sha Awung, spokesperson for the Joint Strategy Team, a coordinating body of nine local and national NGOs leading the humanitarian response in Kachin tells TIME.

La Seng is waiting to hear news of his children, whom he hasn’t seen since they were separated when fighting came to his home.

“My children were on the other side of the village and fled into the jungle. If the fighting stops, they can come back and go freely to school,” he says. “My two children are still in the jungle after six days. There is no phone connection.”

Kachin women build shelters in Kachin state, Myanmar. Fighting between Kachin rebels and the Myanmar army has displaced 5,000 people since early April. Dustin Barter

No access for humanitarian groups

Compounding the problem is the lack of access to those in need, with international humanitarian groups barred from most of Kachin state. The military retains a firm grip on where people can travel, and it can take months to be granted permission for food deliveries to some areas. The U.N. Children’s Fund (UNICEF) said they haven’t been granted access to areas affected by the recent outbreak of conflict and they have seen their access in Kachin decrease overall in the past two years. They are not alone.

Oxfam’s Country Director Paul Joicey said in a written statement, “It is critical that international humanitarian and human rights law is upheld throughout Kachin, with civilian safety the top priority. For civilians caught in conflict areas, safe passage out is urgent.”

No assistance has been able to reach the 2,000 people, many of them children, women and the elderly, who remain trapped in active conflict zones for more than three weeks.

“Their lives are at risk as repeated requests for safe passage and access to deliver life-saving humanitarian assistance continue to be denied,” said a statement from nearly 20 national and international aid agencies released Wednesday. “It is critical that all warring parties uphold the protection of civilians and adhere to international human rights and humanitarian law.”

As well as artillery fire and and bombings, there have been reports of casualties from landmines, which litter the area after years of war.

For the past six years, the government has repeatedly tried to bring the various ethnic rebel armies to the negotiating table, and it was a key issue for Myanmar’s defacto leader Aung San Suu Kyi, who swept to power in 2016 after decades of military rule. But peace efforts have been slow and fighting between the KIA and military has continued. The much-touted transition has failed to reign in the military, which wields power much as it did during the junta days.

The fighting in Kachin state comes after a campaign of ethnic cleansing conducted by the army against the Muslim Rohingya population in western Rakhine state. More than 700,000 Rohingya people fled into Bangladesh after attacks by the military and Buddhist vigilantes, in what the country’s U.N. rights envoy said bears “the hallmarks of genocide.”

A Kachin Independence Army soldier patrols the frontline area on June 16, 2012. Fighting between the Myanmar army and KIA has escalated since early May, displacing 5,000 people in Kachin state. Jason Motlagh—The Washington Post/Getty Images

Rights violations

In a March report, a fact-finding mission by the U.N. human rights council found a “spike in human rights violations and abuses and violations of international humanitarian law” in Kachin and neighboring Shan states. Credible reports said crimes committed by the military in the northern states include indiscriminate attacks, extrajudicial killings, torture, rape and forced labor.

Members of the international community have called for the recent escalation in fighting to stop.

“Innocent civilians are being killed and injured,” U.N. Special Rapporteur for human rights in Myanmar, Yanghee Lee, said in a statement Tuesday. “What we are seeing in Kachin state over the past few weeks is wholly unacceptable, and must stop immediately.”

The U.S. embassy in Yangon said it was “deeply troubled” by the fighting, and urged all parties to end the hostilities. “We call upon the government, including the military, to protect civilian populations and allow humanitarian assistance to be delivered to those affected by the conflicts,” a statement said.

Read More: Myanmar’s Crisis, Bangladesh’s Burden: Among the Rohingya Refugees Waiting for a Miracle

Those seeking shelter in the overcrowded church near Myitkyina are left in uncertainty, with many worried about being forced to return to their villages without guarantees of safety. Their kids are out of school, their rice paddies remain uncultivated, and the monsoon rains are just around the corner, a sign that even more hardship is to come.

“Elderly people and children are trapped. If we are all living in camps, what future do we have?” says a 40-year-old Kachin woman from Injayang township. “I only know suffering.”

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Write to Helen Regan at helen.regan@timeasia.com.