For seven months, Hassan al-Kontar, a Syrian refugee, has been posting videos to social media documenting his life stranded at the Kuala Lumpur International Airport in Malaysia.

Mr. Kontar, who had been working abroad, could not return home because he objected to serving in the military in Syria, a country in the midst of a brutal civil war. He eventually traveled to Malaysia where he thought he could travel onward and seek asylum. But after being turned back in repeat attempts to leave the country, he was stuck.

This week, Mr. Kontar’s ordeal took another turn with his arrest by the Malaysian police, a move that has set off fears among rights groups that he could be forcibly returned to Syria.

Datuk Seri Mustafar Ali, the director general of the Immigration Department of Malaysia, told local journalists that Mr. Kontar, 37, had been staying in a restricted area, according to The Star, a Malaysian news outlet.