A former British ambassador to Myanmar who now heads a business ethics advisory group in the Southeast Asian country has been arrested, reports in the country’s independent online media said on Thursday.

Vicky Bowman, who served as the British envoy from 2002-2006, was detained on Wednesday night and taken to Yangon’s Insein Prison, said a report in Myanmar Now, an online news service. It said her husband, Myanmar artist Htein Lin, was also detained.

The report cited sources close to Bowman’s family as saying she was expected to be charged with violating Myanmar’s Immigration Act.

Myanmar Now, like most of the country’s independent media, is forced to operate underground because of tight controls imposed by the military government.

A friend of Htein Lin, who asked that her name not be used because of fear of government reprisal, told The Associated Press that they were taken by security forces on Wednesday while they were temporarily staying in Yangon. She said they had been living for years in Kalaw township in Shan state in eastern Myanmar.

The reason for their reported detention was not immediately known.

Since 2013, Bowman has been heading the Myanmar Centre for Responsible Business, which says its goals include the promotion of human rights through responsible business in Myanmar. Phone calls to the organisation for comment went answered.

Bowman’s first stint as a diplomat in Myanmar was in 1990-93 as the British embassy’s second secretary.

Htein Lin is an artist and veteran political activist who was a student when he took part in Myanmar’s failed 1988 uprising against military rule. He was also a political prisoner under a past government.

Some reports, including the BBC’s Myanmar service, said only Bowman had been arrested and her husband had then gone to her place of detention to assist her. There were no immediate statements from the military government about the situation.