At least 49 people died in a building fire in Kuwait early on Wednesday, the country's state-run news agency reported.
Officials said the blaze appeared to be linked to regulation violations.
Interior minister Sheikh Fahad Al-Yousuf Al-Sabah confirmed the toll and ordered the arrest of the building's owner during a visit to the site, local media reported.
Local media said scores of workers were living in the building in the southern Mangaf district, without giving their nationality.
Col Sayed Hassan al-Mousawi, head of the firefighters' accident investigation department, said there were dozens of casualties and that the final death toll may be higher.
Kuwait, like other Persian Gulf countries, has a large community of migrant workers who far outnumber the local population.
The nation of some 4.2 million people is slightly smaller than the US state of New Jersey but has the world's sixth-largest known oil reserves.