They are part of a long-simmering conflict that remains largely hidden from the outside world. The fighting has ebbed and flowed across this former British colony for more than 60 years, prompting some observers to describe it as the world's longest-running civil war.

There are no less than 15 different armed rebel groups active in Myanmar. Some of them, like the Kachin Independence Army and the United Wa State Army, have controlled and administered large swaths of territory for years.

This complicated ethnic conflict will likely present one of the thorniest challenges to the government that eventually emerges from last Sunday's historic national elections.

Early election results point to toward victory for Aung San Suu Kyi's National League of Democracy.

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Tension before the election

In the final weeks before the November 8 election, fighting flared between rebels from the Shan ethnic group and the Myanmar military in the north-eastern Shan State. The clashes prompted the country's election commission to cancel voting in several townships just days before people were to go to the polls.

In October, more than 6,000 people fled fighting in this area, according to the United Nations. Some of them ran to the state capital Taunggyi to take shelter with friends and relatives.

It was here that a badly wounded 26- year-old man named Sai Wan lay recuperating in a reclining chair.

He told CNN he was caught in crossfire in his village during a clash between the Myanmar military and rebels from the Shan State Army on the night of October 26.

"The soldiers from the army shot me," he said, pointing at bandages on his stomach and left arm.

"I was bleeding all night," he added. Sai Wan said that his pregnant wife managed to bandage his wounds until he was able to see a doctor eight hours later.

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Nearby, at the office of an ethnic Shan political party, which competed in the elections, a local party official squarely blamed the Myanmar military for the hostilities.

"For 60 years, we have suffered," said Sao Yoon Paing, of the Shan Nationalities Development Party.

"Most of the military are Burmese," he said, naming the country's largest ethnic group.

"They bully the Shan people," he added. "If they leave this area, the war will stop."

In a phone interview with CNN, Presidential spokesman Zaw Htay insisted that the government favored political dialogue with militias. He accused rebels in Shan State of re-igniting the conflict.

"As far as I know, the Shan groups are attacking the bases of the army and fighting each other," Zaw Htay said.

He pointed to a ceasefire that the government negotiated in October.

But only eight out of 15 armed groups signed on to the deal. Factions like the Arakan Army, the ethnic Kokang Myanmar National Democratic Alliance Army and the Ta'ang National Liberation Army weren't even invited to the peace talks.

Soldiers hide in remote mountains

To reach the mountain stronghold of the TNLA, CNN had to travel on bruising dirt roads for hours through the mountains of Shan State.

The treacherous route was clearly vulnerable to landslides, some of which had recently been cleared by road crews. Along the way, CNN passed a patrol of about a dozen light infantry soldiers from the Myanmar military, resting in the shade. One soldier was armed with a sniper's rifle.

The TNLA claims to defend the interests of Myanmar's Ta'an ethnic minority, which they say has a population of about one million.

"We are fighting for the liberation of the Ta'an people and to free them from oppression," said Robert Anyunt, the uniformed rebel who introduced himself as a brigade commander of the TNLA.

He said that the Ta'an people deserve a state of their own within a proposed "federal system" in Myanmar.

Fighting for freedom — and against drugs

The rebels had posted printed signs around the village of Pang Law, as well as a neighboring ethnic Ta'an village, declaring the area a "drug-free zone" based on the authority of the TNLA.

Anyunt said drug addiction has ravaged the Ta'an community. The TNLA was battling it, he said, by arresting and incarcerating drug dealers, opium poppy growers, and drug users.

The TNLA shared propaganda videos with CNN that showed rebels clashing with government soldiers in the mountains.

In one ambush, the fighters appeared to have killed a soldier, leaving his uniformed body splayed out on a dirt road. In another, they handcuffed and publicly humiliated two men in government uniforms who they accused of smuggling narcotics.

According to the United Nations Office on Drugs and Crime, Myanmar is now the world's second largest producer of opium after Afghanistan. Non-governmental organizations report that drug abuse has sky-rocketed over the last decade, particularly in regions populated by the country's ethnic minorities.

In the past, some of the armed rebel groups have been implicated in illegal narcotics production and sales.

"There are no angels in this fight," a senior U.S. government official told CNN, speaking on condition of anonymity due to official protocol.

National vs. ethnic identity?

The official described the ethnic conflict as part of an existential question Myanmar has struggled with since becoming an independent country in 1948.

"Since independence, they have never really determined the definition of national identity, as well as the distribution of resources," the U.S. official said.

Ethnic identity appears to be a major motivating factor for armed groups like the TNLA.

"We felt we were slowly being weeded out and in danger of seeing our ethnicity disappear," said Anyunt, the 31-year old TNLA commander.

He spent the last 11 years -- almost all of his adult life -- as a TNLA fighter. The organization pays each rebel a salary of around $9-a-month, he said.

"We aren't the only ethnic group fighting against the Burmese government," Anyunt added.

"The only way to protect your community is to have your own army."

At sunset, thick clouds blew across the mountain peak, enveloping the village of Pang Law. As dusk fell, dozens of uniformed rebels returned to the village after completing a day of patrols in the surrounding jungle.

The village has no paved roads or electricity. The only sign of any government presence was a school with dirt floors and no text books.

For the time being, the ethnic Ta'ang rebel represents the only law in this mountainous land.

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