The gunfire in the city of Mandalay began shortly after 7 a.m. on Tuesday, as Buddhist monks paced the streets for alms and residents lined up for breakfasts of milk tea or noodle soup.
Mandalay, the second-largest city in Myanmar, has been a center of anti-military resistance since the junta staged a coup on Feb. 1. Dozens have been shot dead by security forces there. But the boom of heavy artillery so early in the morning was unusual.
The volleys of gunfire marked the first time that clashes erupted in a big city between the military and a newly formed militia, the People’s Defense Force, affiliated with Myanmar’s ousted elected leadership.
“We have started and declared war,” said Ko Tun Tauk Naing, a spokesman for the People’s Defense Force in Mandalay.
The shootout began after soldiers from the Tatmadaw, as the Myanmar military is known, raided a building where members of the civilian resistance were sheltering, according to accounts from both sides. A Tatmadaw television network said that explosives were being stored in the building. Unexplained bombings targeting symbols of the state, such as local government offices or military-linked businesses, have proliferated across the country in recent weeks.
Both the Tatmadaw and the People’s Defense Force claimed casualties on the opposing side and denied deaths among their forces. On pro-military social media accounts, users posted photos of a row of bloodied corpses, most stripped down to their underwear. The dead were identified on a military television network as “terrorists” who had opposed the State Administration Council, as the junta calls itself. Four were killed in battle and four others died when their car crashed as it tried to escape the shootout, the military network said.
But members of the People’s Defense Force denied that any of their ranks had died and said that eight Tatmadaw soldiers had been killed.
With sporadic gunfire resounding through Mandalay for much of Tuesday, the People’s Defense Force urged solidarity, pleading for residents to burn tires on the roads to slow the arrival of armored vehicles. Columns of soldiers were deployed from nearby military bases, including one established on the requisitioned grounds of the former royal palace in the heart of Mandalay.
“The Mandalay P.D.F. needs the assistance of the people,” said Bo Zee Kwat, a local resistance leader. “We need the people’s cooperation urgently.”
On Tuesday afternoon, the United States Embassy in Myanmar posted on Facebook about the clashes in Mandalay.
“We are disturbed by the military escalation and urgently call for a cessation of violence,” the post said, expressing concern about possible civilian casualties.
Cobbled together in the wake of the coup by civilians loyal to the ousted government and other democracy activists, the People’s Defense Force has been receiving military training in border areas controlled by ethnic insurgents. In videos from these remote forests, recruits are seen marching with rifles, their newly made uniforms decorated with the insignia of the People’s Defense Force.
Myanmar is one of the most militarized societies in Asia, and the army has run the country for most of its modern history. The Tatmadaw claims half a million soldiers, although its true fighting force is much smaller, according to military experts. For the People’s Defense Force to battle such a large army, it will have to depend on insurgency tactics, according to defense experts who have been advising the resistance movement.
Armed resistance groups, composed of fighters belonging to the People’s Defense Force and more formally trained ethnic insurgents, have tried to take on the military in parts of the country where ethnic minorities are concentrated. As it has elsewhere in the country, the Tatmadaw has violently crushed peaceful protests in the ethnic-minority regions, shooting children and unarmed marchers.
Two sustained strongholds, in Chin State in the west and Kayah State to the east, eventually crumbled with civilians killed and towns overrun. In one case, people sheltering in a church were attacked by Tatmadaw soldiers, according to residents. Thousands of people have been forced to flee into the forest.
But the Tatmadaw has suffered heavy casualties, too, according to the People’s Defense Force and military insiders. Hundreds of soldiers have been killed in fighting since the coup, they said.
In the country’s mountainous periphery, armed ethnic groups have been battling for autonomy for decades, and they have provided jungle training to doctors, massage therapists, engineers, beauty pageant competitors, Buddhist monks and thousands of others who have left the cities to join the armed resistance. Some of the recruits have since traveled back home with secret missions.
As members of the Mandalay People’s Defense Force tried to melt into the neighborhood on Tuesday, Tatmadaw soldiers went from house to house, firing into gardens and at balconies, witnesses said.
Soldiers patrolled the entrances to three city hospitals, presumably to capture any wounded militia members who might be brought in for treatment. Underground medics, some of whom have been jailed for their efforts and paraded on television with visible bruises, roamed the city looking for the injured to treat.
One medic said that Tatmadaw soldiers had fired at a young man on a motorcycle who was passing through the conflict zone while carrying a bag of rice on Tuesday morning. He is being treated in a secret location, the medic said.
Outdoor eateries and tea shops in the eastern Mandalay neighborhood where the fighting broke out were deserted. Residents hid behind curtains, daring occasionally to record shaky video of the exchanges of gunfire on their phones. In the west of the city on Tuesday afternoon, semiautomatic gunfire again crackled. Unexplained explosions rocked at least four other parts of town.
The People’s Defense Force said that at least six of its members were arrested in Mandalay on Tuesday and that an unspecified number had been injured.
“We had to give up some of our people this morning,” Mr. Tun Tauk Naing, the spokesman for the People’s Defense Force, said. “But we still have a lot of men. We won’t give up.”