The death toll is now two from a house fire this weekend in Rochester, authorities said Sunday.

The blaze was reported to 911 dispatch shortly after 8 p.m. Friday at a single-family home at the intersection of 10 ½ Street and 11th Avenue SE., according to fire officials.

Friday's death of Barbara Ruth Thoreson, 51, was announced Saturday. Her son, Matthew Thoreson, 26, died later Saturday after being hospitalized, Deputy Fire Chief Steve Belau said Sunday afternoon.

Firefighters encountered heavy smoke while entering the home, then found the woman dead in the living room, the Fire Department reported. Firefighters removed the man from the house; he was hospitalized in critical condition.

The blaze was considered under control within about 15 minutes. The circumstances leading up to the fire have yet to be released.

"The fire had been burning for an extended length of time before smoke became apparent to passersby who had made the initial calls to the 911 center," the Fire Department said in a statement. The house was heavily damaged.

Capt. Craig Connelly, who was among those fighting the fire, said, "It's just so frustrating when we can't save everyone."

Hot weather made fighting the blaze particularly difficult. Belau noted that the firefighters' protective clothing creates the effect of a "hotbox sauna with 100 percent humidity."