LONDON — Shamima Begum, the 19-year-old Briton who married an Islamic State fighter four years ago and recently asked to be allowed to return home, has been forced to move from her place in a Syrian refugee camp with her newborn after receiving threats, her family’s lawyer said on Friday.

British media outlets reported that Ms. Begum may have been moved to another refugee camp closer to the border with Iraq. But in a phone call on Friday afternoon, the lawyer, Tasnime Akunjee, said: “We don’t know where she has been moved to. We don’t know if it’s within the camp or to another one.”

The new development adds to the uncertainty surrounding a case that has split opinion in Britain. Some Britons have said that Ms. Begum was so young when she left to join the extremists that she deserves a chance at rehabilitation. Others have called for her never to be allowed back in Britain again.

The British newspaper The Sun was the first to report the threats against Ms. Begum in Al Hawl refugee camp in northeastern Syria, where she fled to several weeks ago from the last remaining village held by the Islamic State in Syria.