A mother and her son and daughter - all recent immigrants to Salt Lake City from Vietnam - were killed Friday night in a car rollover on I-15, 10 miles north of Beaver, a Utah Highway Patrol spokeswoman said.

The family's father and two other siblings were hospitalized after the accident.Thanh Nguyen, 43, her 16-year-old son, Hut, and 9-year-old daughter, Nai, died in the accident. Khan, her 14-year-old son, was in serious condition in LDS Hospital Saturday night, a hospital official said.

Phep Nguyen, 43, the father, and his 12-year-old daughter Thuy were in good condition in Beaver Valley Hospital, Beaver, a hospital official said Saturday.

The father was at the wheel of the family vehicle about 10 p.m. Friday when he swerved to avoid hitting a deer, rolling the vehicle three times, the UHP spokeswoman said.

Authorities said it was difficult to contact relatives of the family.

"It was really hard talking to the father because he didn't speak English. My first impression was that they had no relatives in the United States," said Trooper Dean Kay, who investigated the accident.

But officials were able to learn of a relative in San Francisco and also were able to contact the family's immigration sponsor, who traveled to Beaver Saturday to help the family, Kay said.