The students, a boy and a girl, were participating in the lunchtime Spirit Week activity celebrating homecoming Monday afternoon when their fingers were torn off.
The pair underwent surgery yesterday and are currently in stable condition, USC Medical Center Spokeswoman Rosa Saca said.
"At this point, I cannot disclose the outcome of the surgery, but this morning the kids are in stable condition," Saca said.
El Monte Union High School District officials have not released the students' names or ages.
The girl is a senior and varsity soccer player, and the boy is a senior football player.
Authorities and district officials have not released information as to many fingers the girl and the boy each lost.
The students were participating in the lunchtime Spirit Week activity celebrating homecoming.
"All of our schools celebrate homecoming, so they have different activities on campus," Superintendent Nick Salerno said. "That was one of the activities planned for the week."
The rope reportedly snapped in half when the students were injured, Salerno said.
District officials said it is unknown how many teens were participating in the tug-of-war.
Salerno said the district is in disbelief over the incident.
"When I was a student, I was in those games myself many times," he said. "I've seen the activity many times at schools and venues and I've never heard of this happening. Disbelief. Shocked. Sad."
"Right now our focus is on helping students," Salerno said. "The counseling started yesterday and will continue today and it will continue as long as we need to."
It is unknown whether the school or El Monte Union High School District will change policies on campus activities.
"It's a high probability we won't be having tug of wars," Salerno said.