VICTORVILLE, Calif. — An 18-year-old high school student has been arrested and charged after investigators discovered he was planning a school shooting in Southern California and researched police response times.

Sebastian Villasenor, of Eastvale, California, was charged Wednesday with multiple felony counts related to a planned attack on Ontario Christian High School in Ontario, California, a city about 46 miles east of Los Angeles, according to the San Bernardino County District Attorney‘s Office. The charges include five counts of attempted murder and one count of attempting to make criminal threats.

Villasenor was arrested on Feb. 10 after a classmate reported that the teen "had been showing signs of being fixated on school shootings and had access to weapons," Ontario Police Chief Michael Lorenz said at a news conference Wednesday.

"Thanks to the swift and thorough response of the Ontario Police Department, and the bravery of the student who voiced concerns, tragedy was avoided and potentially lives were saved," the San Bernardino County District Attorney‘s Office said in a news release.

Police chief: Student 'obsessed with our response times'

Investigators found that Villasenor, who has no prior criminal record, "had every intention of carrying out a school shooting at the Ontario Christian High School," according to Lorenz.

Lorenz added that the teen was "obsessed" with school shootings and police response times. He also researched tactical supplies and was in the process of choosing a date for his attack.

"He was so obsessed with our response times that he Google mapped how far it would be from the Ontario Police Department for our response time to the school," Lorenz said.

Investigators believe Villasenor may have been planning a shooting around April 20, which is the anniversary of the 1999 attack at Columbine High School in Colorado that left 15 people dead, including the two shooters.

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Investigators discovered arsenal of weapons in teen's home

While searching Villasenor’s home, Lorenz said authorities collected "numerous weapons," including seven rifles, two revolvers, a handgun, and a shotgun along with more than 1,000 rounds of ammunition.

Although Villasenor didn’t have a "hit list," Lorenz said further investigation led police to believe that he was focusing on five students as intended victims and “contemplated” a sixth victim, based on interviews regarding his social interactions with the students.

All the victims were students at Ontario Christian High School, according to Lorenz.

Investigators determined that Villasenor wasn’t “bullied or harassed” but had difficulties “forming relationships with other students and in his social interactions.” Villasenor is in custody at the West Valley Detention Center in Rancho Cucamonga.

He is ineligible for bail, sheriff’s records show. He was arraigned Thursday and pleaded not guilty to all charges, according to the district attorney’s office.

Contributing: The Associated Press

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