Two Los Angeles-area high school students had fingers severed while taking part in a "spirit week" group tug-of-war contest, authorities said on Tuesday.

A boy and a girl from South El Monte High School were rushed to a local trauma center on Monday afternoon after their fingers were cut off during the tug-of-war at lunchtime, fire and school district officials said.

The students have undergone surgery to reattach the severed digits, El Monte Union High School District Superintendent Nick Salerno said.

"I'm a dad too, and my heart goes out to these kids and their families. To me the whole thing is unbelievable," Salerno told Reuters. "I've been in tug-of-wars myself, more than I can even count, and I've never heard anything like this."

Salerno said the two teens, who have not been identified by authorities, were both student athletes participating in annual activities designed to boost school spirit and participation.

"The activity that day was tug-of-war. Unfortunately the rope broke and both students had some fingers severed," he said, adding that he had no further details on how the injuries occurred.

A spokesman for Los Angeles County-USC Medical Center said both students were listed in stable condition. He declined to elaborate on their condition or the outcome of the surgery.

Salerno said the school district had provided counseling for students at South El Monte High School, which serves about 1,500 students in El Monte, a city of about 115,000 people in the San Gabriel Valley north of Los Angeles.