A BBC journalist invited to Qatar to examine the living conditions of workers building infrastructure for the 2022 football World Cup was detained for more than 24 hours, the broadcaster reported Monday.
Mark Lobel, a BBC business correspondent based in Dubai, said he and colleagues were detained in the capital Doha as they went to film a group of Nepalese labourers earlier this month.
It is the second time in weeks that Qatari authorities have arrested journalists attempting to report on the living conditions of the Gulf emirate's large migrant workforce.
In March, a German television reporter and colleagues were detained while filming in an area of Doha where many labourers live.
The arrests come as Qatar is engaged in a public relations drive to try to counter international criticism of its treatment of migrant workers.
Lobel said he and three colleagues were held for more than 24 hours, spending two nights in prison.
He was then prevented from leaving the country for almost a week.
No charges were laid against the BBC crew but their equipment and belongings were confiscated and have not yet been returned.
He wrote on the BBC News website that the arrest was "dramatic".
"Suddenly, eight white cars surrounded our vehicle and directed us on to a side road at speed," he said.
"A dozen security officers frisked us in the street, shouting at us when we tried to talk. They took away our equipment and hard drives and drove us to their headquarters.
"Later, in city's main police station, the cameraman, translator, driver and I were interrogated separately by intelligence officers. The questioning was hostile."
After their release the BBC crew were allowed to join the official press tour, organised by a London-based public relations company, Portland Communications.
Government Communications Office chief Saif Al-Thani accused Lobel of breaking Qatari laws and making "himself the story".
Thani said that without waiting for the government's scheduled tour, the BBC crew had tried to break into a workers' camp at night.
"In doing so, they trespassed on private property, which is against the law in Qatar just as it is in most countries," he said in a statement.
"By trespassing on private property and running afoul of Qatari laws, the BBC reporter made himself the story. We sincerely hope that this was not his intention."
Human Rights Watch's Gulf researcher, Nicholas McGeehan, tweeted that Qatar's arrest of the BBC team was "jaw-droppingly awful PR".
The Qatari government has claimed in recent weeks that it is improving conditions for migrant labourers.
It has introduced a wage protection system to ensure workers get paid on time and is building several new residential neighbourhoods to improve living conditions.
It has also said it is soon likely to end the controversial kafala system, under which foreign workers must have a Qatari sponsor, which critics have likened to modern-day slavery.