Four students from a high school in Northern California have been arrested for plotting an attack against Summerville High School in Tuolumne, authorities announced Saturday. The students, all of whom were males, reportedly had a detailed plan to shoot and kill students and teachers at the school, the New York Times reported.

The suspects "were going to come on campus and shoot and kill as many people as possible," Sheriff James W. Mele of Tuolumne County, who did not identify the students, said in a news conference Saturday, according to the Times. "The suspects’ plans were very detailed in nature and included names of would-be victims, locations and methods in which the plan was to be carried out." 

Mele also said that the students "were in the process of trying to obtain" the weapons required to conduct the attack. A clear motive for the planned attack was not yet found.

Three of the arrested students were overheard discussing the attack on the school Wednesday, following which the school administration was informed and police was called. The fourth suspect was identified during the investigation. The exact time of the planned attack was not revealed, but Mele reportedly said that the attack was expected to be conducted during a school event.

"Within two to three minutes, those administrators got up out of their seat, recognizing the severity of the information that they received, and were in the classroom pulling those students out," Robert Griffith, the superintendent of the Summerville Union High School District, said, according to the Times.

"As each one of them was identified they were removed from campus," Griffith was quoted by the Washington Post as saying. "Their parents were called."

Police officials reportedly planned to call the parents of the students whose names were on the hit list made by the suspects. The plot against the high school in Tuolumne, about 120 miles east of San Francisco, was foiled a day before nine people were shot dead in Umpqua Community College in Oregon by a 26-year-old man, who later allegedly committed suicide.

"It is clear from past history, such as Columbine and Sandy Hook, as well as other recent events in Oregon, that children are willing and capable of planning and carrying out acts of violence against fellow students and teachers on school grounds," Eric Hovatter, Tuolumne County assistant district attorney said, according to KCRA. "While it is easy to say that can never happen in Tuolumne County, the public and local law enforcement must be vigilant, as they were here."