Three 13-year-old girls dressed in Halloween costumes and carrying bags of candy were killed by a hit-and-run driver while trick-or-treating in Santa Ana, Calif., on Friday evening, the authorities said.

The girls, two of whom were twin sisters, were crossing the street in the 1400 block of East Fairhaven Street when they were struck around 6:45 p.m., said Capt. Steve Concialdi, the spokesman for the Orange County Fire Authority.

Two of the girls were dead when paramedics arrived at the scene, Captain Concialdi said. The paramedics tried to save the third girl, but she died minutes after they arrived, he said.

“Here is a night where they were supposed to be celebrating and having a good time, and it ends up in tragedy,” Chief Carlos Rojas of the Santa Ana Police Department said. “It’s a horrible situation.”