Army chief Ye Win Oo is a close confidant of Senior General Min Aung Hlaing -- leader of a 2021 coup that plunged the country into civil war -- and was tapped on Monday to take over his role as commander-in-chief of the armed forces.

Min Aung Hlaing is expected to soon swap his military uniform for civilian dress, becoming president in a move critics call an attempt to maintain power by crafting a democratic facade.

General Ye Win Oo, who often accompanies Min Aung Hlaing on official foreign visits, typically remains discreet and behind the scenes.

But in recent months he has been seen in public more, alongside other top generals, including at an event in the capital Naypyidaw this weekend marking one year since a massive earthquake killed more than 3,800 people in the country.

AFP journalists also saw Ye Win Oo in traditional civilian clothes, guarded by military police, as he voted at a polling station in Naypyidaw alongside his wife and daughter during the first phase of a junta-orchestrated election in December.

All three have been sanctioned by the United States and the European Union over his alleged role in the putsch.

Local media has reported Ye Win Oo personally led a raid on the Naypyidaw residence of democratic figurehead Aung San Suu Kyi on the first day of the February 2021 coup, which saw the Nobel Peace Prize laureate detained and her popular party dissolved.

Just this month, Min Aung Hlaing promoted Ye Win Oo to the army's top leadership position, after he had served as head of military intelligence for years.

This put Ye Win Oo in one of the nation's highest military roles, taking over from Soe Win, who was deputy military chief until he was replaced on Monday.

- 'Dark history' -

Ye Win Oo's advancement had sparked speculation among analysts and the public that he was being groomed to become the armed forces commander -- just as the country prepares to form a new government after pro-military parties handily won the heavily restricted election.

"Defined by his unwavering loyalty and close personal ties to the Senior General, Ye Win Oo will likely steer the military to prioritize Min Aung Hlaing's interests," said Naing Min Khant, a researcher at the Institute for Strategy and Policy Myanmar think tank.

Their close relationship dates back more than two decades to Ye Win Oo's time as a battalion commander serving under Min Aung Hlaing, who was then a regional commander of forces tasked with defending the borders with Thailand and Laos in eastern Shan state.

Ye Win Oo, 60, has been widely described by analysts and local media as the "eyes and ears" of Min Aung Hlaing, having served as chief of military intelligence from 2020 until this month, according to local media reports.

"General Ye Win Oo has a dark history," Naing Min Khant told AFP, explaining that he "earned a reputation for brutality against the democratic opposition" during his time as spymaster.

Ye Win Oo's ascent within the junta has been rapid, beginning with his appointment as joint secretary of the State Administration Council just one day after the February 1, 2021 coup.

He was promoted to the rank of general in August 2024 and became the secretary of the 10-person State Security and Peace Commission junta body in July.

While thousands of young people have fled Myanmar following the enactment of the conscription law, Ye Win Oo's son, Htet Ye Naung, reportedly completed his own military training last year alongside drafted recruits -- with his parents attending the graduation ceremony.