The UK's former ambassador to Myanmar and her husband have each been sentenced to one year in prison by the country's military authorities.

Vicky Bowman and Htein Lin, a former political prisoner, were charged with breaching immigration laws.

The couple were arrested last week in their home in Yangon.

The case is likely to be about wider political concerns than immigration offences, for which foreigners are rarely prosecuted in Myanmar.

Ms Bowman, a fluent Burmese speaker, is a well-known member of Myanmar's small international community.

She first served in what was then called Burma in 1990 as a junior diplomat and returned as ambassador from 2002-2006. She now runs the Myanmar Centre for Responsible Business (MCRB), based in Yangon, which said it was "shocked" by the sentences.

In its statement, it added that Ms Bowman had "dedicated many years of her life to strengthening social and economic development in Myanmar".

"We hope it will be possible for her to be reunited with her family in the UK soon," it said.

Ms Bowman and her husband were detained when they returned to the city from a home they have in Shan State. Military authorities charged them both with failing to register her as living at a different address.

Htein Lin is a prominent artist and former political prisoner who was a member of the All Burma Student's Democratic Front, an armed resistance group which was formed after the popular student-led uprisings against the military junta in 1988.

The couple got married and moved to London before returning to Yangon in 2013.

The pair's arrest came as the UK recently announced sanctions against the military authorities in Myanmar - coinciding with the fifth anniversary of its deadly crackdown on Rohingya Muslims in the country. The onslaught in 2017 left more than 6,000 people dead, and displaced hundreds of thousands in just the first few months, with most of them fleeing across the border into Bangladesh.

Earlier on Friday, a military-run court in Myanmar also sentenced former leader Aung San Suu Kyi to a further three years in jail on election fraud charges.

Myanmar's military regime has been accused of widespread violations of human rights.

Early in August, generals extended their emergency rule until 2023, with the country riven by internal fighting.

The junta seized power last year after overthrowing Aung Sung Suu Kyi's democratically-elected government.

After last year's coup Ms Bowman chose to stay in Myanmar, and appears to have been careful to avoid any public comment which might provoke the military government.

Her conviction is widely assumed to be driven by something other than a minor breach of immigration rules.

Many foreigners have overstayed visas, often by many months, or changed addresses without notifying the authorities, but prosecutions for such offences are almost unheard of in Myanmar. Usually a small fine will settle the matter.

But as perhaps the best-known British national still living in Myanmar after the coup, Ms Bowman is likely seen by the junta as a suitable target for retaliation against the British government.

The UK has taken a hard line against the military rule, and the current UK ambassador was expelled from the country.

It's also possible the junta feared her work led her to sensitive information or detailed knowledge about the opaque workings of shady military-linked companies.

Ms Bowman has also been critical of some of the measures taken by the junta which have affected the economy; she has spoken at numerous seminars on Myanmar since the coup, though generally she has been careful to avoid any open criticism of the military government.

Her husband may also be a factor in their arrest. Htein Lin was a prominent member of the so-called 88 generation of dissidents who spent six years in prison in the early 1990s, though in recent years he has kept a lower political profile and been better known as an artist.