A fire raged through a 12-story hotel at a popular ski resort in northwestern Turkey early Tuesday during a school holiday, killing at least 76 people — at least two of them when they jumped from the building to escape the flames, officials said.

At least 51 people also were injured in the fire at the Grand Kartal hotel in Kartalkaya, in Bolu province’s Koroglu mountains, some 300 kilometers (185 miles) east of Istanbul, said Interior Minister Ali Yerlikaya. The fire occurred near the start of a two-week winter break for schools, when hotels in the region are packed.

“Our hearts are broken. We are in mourning, “Yerlikaya told reporters outside the hotel. “But you should know that whoever is responsible for causing this pain will not escape justice."

Atakan Yelkovan, a hotel guest staying on the third floor, told the IHA news agency there was chaos on the upper floors as other guests tried to escape, including by trying to climb down from their rooms using sheets and blankets.

“People on the upper floors were screaming. They hung down sheets ... Some tried to jump,” Yelkovan said.

Yerlikaya said 45 of the 76 people killed have been identified while efforts to identify the other victims were continuing.

“Forty-five bodies were delivered to their families. We could not (immediately) identify the others,” Yerlikaya said, adding that the emergency response teams would conduct a final search for victims on Wednesday.

Health Minister Kemal Memisoglu said at least one of the injured was in serious condition, while 17 other people were treated and released.

The hotel had 238 registered guests, Yerlikaya said. The fire was reported at 3:27 a.m. and the fire department began to respond at 4:15 a.m., he told reporters.