Authorities believe the two male students, ages 15 and 16, were the only ones involved in the plot, and police said they admitted planning to shoot fellow students during an upcoming assembly.
"We had no idea. This is Covina. This doesn't happen here. It's small. No one does this here. It's shocking," said student Stephanie Comstock.
School was back in session on Friday, but it was anything but a normal day, as the halls buzz with news of the arrests.
"I think it's pretty scary, since nothing like this has ever happened around this school or around the area," said student George Fuentes.
The two boys are residents of West Covina, and West Covina police officers recovered two handguns and ammunition from the 15-year-old's home on Thursday.
The weapons were hidden under a bed, police said, and at least one of the guns was loaded.
The stepfather of the 16-year-old had reported to police that two guns were stolen from a locked safe at his home.
Their investigation quickly turned to the stepson, who police said admitted to prying open the lock about a month ago and giving them to his friend. The teens also said they took the guns to school three times in the last month and even showed them to other students.
"The reason why no one reported it is because the few kids they did show it to, they were their best friends, and they felt like they didn't want to get them in trouble, and they were afraid," said principal Claudia Karnoski.
Both teens were arrested Thursday.
"I'm in complete shock right now. With everything going on, I'm really shocked they didn't notify me yesterday," said parent Denise Billiter.
Student Kevin Park said the majority of students had no idea what had happened.
"I think they probably just got them and took them away 'cause, no sirens, no cop cars, we didn't see anything," Park said.
The teens are being held on suspicion of gun possession, making criminal threats and burglary charges.
Police do not know when the teens had planned to carry out the attack and said the teens were planning to shoot indiscriminately.
While authorities do not believe the school is in any further danger, there will be patrols on hand at the school to keep everyone's minds at ease.
"It makes me feel bad for the people more that they have such hatred for life, and such hatred for people that they don't really care what happens," said student Brittney Baca.
Eyewitness News reports Amy Powell and Leslie Sykes contributed to this report.
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