The second San Francisco firefighter badly burned while battling a fire on Thursday has died.
Fire Chief Joanne Hayes-White said that 53-year-old Tony Valerio succumbed to his injuries Saturday, two days after a fire at a four-story home at 133 Berkeley Way in Diamond Heights claimed the life of his colleague Lt. Vincent Perez, 48.
Hayes-White said that during her 21-year career the department had not had two firefighters killed in the same blaze.
"It is particularly difficult. You're mourning the loss of one and then to have another one very close from the same fire is challenging for us, is painful for us," she said.
San Francisco Mayor Ed Lee said in a statement he was "deeply saddened" by the deaths and called the loss a "terrible tragedy" for the city.
"These two men have dedicated their lives to protecting the people of San Francisco for decades," Lee said.
He added that the deaths of Valerio and Perez were a reminder of the sacrifices firefighters and their family and friends make.
"We are forever appreciative for the brave men and women of the San Francisco Fire Department who put their lives on the line every day for us," he said.
Lee joined Hayes-White to announce Valerio's death this morning at San Francisco General Hospital, where both men succumbed to their injuries.
Perez died about an hour after firefighters responded to the blaze at 10:45 a.m., while Valerio remained in critical condition until this morning.
Valerio's heart had stopped by the time he had arrived at the hospital, trauma surgeon Dr. Andre Campbell said. Valerio was suffering from smoke inhalation, burns and other injuries caused by the blast -- including serious lung damage.
"This was a minute-to-minute struggle for his life," Campbell said. In the end, he said, Valerio's injuries were "just too overwhelming."
The two men were badly burned when objects in the room they were in heated to the point of ignition, a dangerous phenomenon known as "flashover," fire department spokeswoman Mindy Talmadge said.
A female firefighter also suffered smoke inhalation while fighting the blaze.
The cause of the fire was still under investigation, and Hayes-White said the department would be reviewing its standard operating procedures in light of the deaths.
Valerio began working for the city 27 years ago as a paramedic, Hayes-White said. He joined the fire department in 1997.
Family members also in attendance Saturday recalled Valerio -- the oldest of his family's seven children and a native of San Francisco -- as an easygoing friend to everyone with a good sense of humor who loved to travel.
His brother Mark Valerio described a time when the two were on a beach in Santa Cruz on a day off when a person in the water was attacked by a shark. Valerio said his brother was the first to rush to the victim's aid.
"He knew that he liked helping people," Valerio said. "He was very selfless."
Dozens of firefighters stood at attention and saluted as Anthony Valerio's body was brought out of the hospital on a gurney draped in an American flag.
On Thursday, Lee ordered that all flags at city-owned sites be flown at half-staff in honor of the firefighters, while Gov. Jerry Brown ordered the same for flags at the state Capitol in Sacramento.
San Jose firefighters also lowered their flags to show solidarity with the San Francisco Fire Department, fire Capt. Scott Kouns said.
This story is based on reporting by Bay City News Service and the Associated Press.