STRESA, Italy — The crash of a cable car near picturesque Lake Maggiore in northern Italy, killing 14 people, occurred after a cable snapped and an emergency brake failed, investigators said Monday.

The cable car had almost reached the end station on Mottarone mountain, a nearly 5,000-foot peak, on Sunday afternoon when it suddenly started sliding backward. It slid for hundreds of meters at a height of nearly 40 feet, hitting a pillar and plunging to the ground. There was only one survivor, a 5-year-old boy.

Hikers and local residents said they heard a hissing sound, presumably when the cable snapped and twisted through the air, and then a loud bang.

“A cable broke and the car slid toward the valley without it being stopped by the braking system,” Olimpia Bossi, the lead prosecutor in the nearby city of Verbania, said in a phone interview. “We are trying to determine why this happened and what broke first.”

Ms. Bossi said that investigators were looking into possible charges against the operator of the funicular cable car, the maintenance company and other unspecified entities including manslaughter, attempted manslaughter and violations of safety measures resulting in a public transportation disaster. No one has been charged so far, and investigators are still evaluating different hypotheses, she said.

“This is a terrible moment for me, for my community, for Italy as a whole,” said Marcella Severino, the mayor of Stresa, the lakeside town where the cable car begins.