Nearly two months after she was arrested on the streets of Somerville and sent to Louisiana to await deportation, Rümeysa Öztürk returned to Massachusetts on Saturday night.

A federal judge on Friday ordered the immediate release of Rümeysa Öztürk, a Turkish Ph.D. student at Tufts University who had been held for six weeks in an immigration detention center, ruling that her arrest and continued confinement were unlawful and raised serious constitutional concerns.

The Tufts University PhD student from Turkey was detained six weeks ago in Somerville by U.S. Immigration and Customs Enforcement.