BUFFALO, N.Y. — Investigators are looking into what caused a fire that killed a father and his two adult daughters in North Buffalo early Monday morning.

Police say Jonathan Daniels, 53, Jordan Daniels, 27, and Jensen Daniels, 23, died in the fire.

The fire at the Huntington Avenue home started on the second floor and spread to the attic, according to fire officials. Firefighters found the victims in the attic and on the second floor, Fire Commissioner William Renaldo said.

The mother, Janessa Daniels, 53, is being treated for smoke inhalation at ECMC and is expected to recover.

Five firefighters were also treated for minor injuries and released. Authorities say a dog also died in the fire.

The family is part of the University at Buffalo community. UB says Dr. Jonathan Daniels served as the associate director of admissions in the Jacobs School of Medicine and Biomedical Sciences.

Jordan was a recent graduate of the university, receiving her MBA in May. Janessa served as UB's senior associate director of financial aid.

The university is providing counseling services for faculty, staff and students.

The cause of the fire is still under investigation.