European diplomats have been photographed at the home of a Nobel Prize-winning writer in Belarus after she said masked men tried to break in.
Svetlana Alexievich called journalists to her home on Wednesday after the incident.
She is the last leading member of the opposition Co-ordination Council still in Belarus who has not been detained.
The government has cracked down on dissent after protests swept the country following a disputed election.
Her lawyer told local news site Tut.by that she was being held on suspicion of calling for “the seizure of state power”.
And on Wednesday witnesses reportedly saw Maxim Znak, a lawyer and another member of the Co-ordination Council, being led down a street in the capital Minsk by masked men in plain clothes.
Thousands of people have been arrested in the crackdown on the opposition and its supporters.
What’s the latest on Svetlana Alexievich?
“Harassments, arrests [and] forced exile of opposition… is a serious violation of peaceful protests,” she said. “Happy to share this photo taken a moment ago in Minsk.”
The opposition set up the committee in the wake of the election calling for a peaceful transfer of power.
“We were not preparing a coup. We wanted to prevent a split in our country,” she wrote. “It was not the [council] that revolted. The country revolted.”
And what happened to Maxim Znak?
The 39-year-old, who previously worked as a lawyer for jailed presidential candidate Viktor Babaryko, was due to take part in a video call on Wednesday but failed to dial in.
When a colleague called him, Mr Znak said someone had arrived and then hung up.
He then texted the word “masks” to a group, one activist told local media. This is believed to be a reference to the face masks worn by the Belarusian security services.
Witnesses then reported seeing Mr Znak being led down a street close to his offices by masked men in civilian clothes.
On Monday, Mr Znak had told the BBC he was concerned about his safety.
“I’m pretending to be relaxed,” he said. “It’s a professional habit – but actually I’m very concerned and scared.”
The police are yet to comment on reports of his detention.
What else is happening?
On Wednesday, the exiled opposition leader Svetlana Tikhanovskaya visited the Polish capital Warsaw where she delivered a speech at a university and called for the protests in Belarus to remain peaceful.
“I think it is impossible to fight violence and give violence,” she said.
She has also called for the immediate release of Mr Znak.
“The methods employed by the so-called authorities are outrageous,” she said in a statement. “It’s clear Lukashenko is afraid of negotiations and is trying… to paralyse the work of the Co-ordination Council and intimidate its members.”
Ms Tikhanovskaya, the chief opposition rival to Mr Lukashenko in last month’s election, was forced to go into exile in neighbouring Lithuania shortly after the vote.
She entered the race after her husband Sergei Tikhanovsky and another candidate were jailed.
Mr Lukashenko, meanwhile, is set to meet Russian President Vladimir Putin on 14 September. The pair will discuss energy co-operation, regional conflicts and many other topics, the RIA news agency reports.