A college student who attacked four people at a University of California campus in 2015 appears to have been “self-radicalized” and was inspired by terrorist propaganda from the Islamic State (Isis), the Federal Bureau of Investigation announced on Thursday.

On 4 November, Faisal Mohammad, 18, stabbed a fellow student in a University of California, Merced classroom and proceeded to attack three others as he fled on campus before police shot and killed him, according to the FBI’s account.

The bureau’s investigation found that his laptop contained “pro-Isil propaganda”, using an alternative acronym for the extremist group. Also officials said he “had visited Isis and other extremist websites in the weeks prior to his attack”.

Mohammad, a US-born son of a couple from Pakistan, allegedly began preparing for the assault at least one week in advance, and FBI officials said that it appeared he was working alone.

At the time of the stabbings, Mohammad was carrying a backpack with a two-page, handwritten plan “detailing his intentions to include taking hostages and killing students and police officers”, the FBI division in Sacramento said in a statement.

Mohammad, a freshman from Santa Clara, California, was also carrying a photocopy of an Isis flag and a list of items that he thought he would need for an attack, including zip ties, a glass breaker and a knife.

Sheriff Vern Warnke of Merced County said at a news conference that Mohammad planned to go into a classroom, tie his classmates’ hands with zip-tie handcuffs and force another student to help him. He allegedly also planned to make a “kind of a slip-and-slide” with petroleum jelly that would make it challenging for people entering the room to get around, according to Warnke.

All of the victims survived the attack.

The FBI added in its statement, “After an extensive investigation of all available evidence, no ties to co-conspirators or foreign terrorist organizations have been found. Every indication is that Mohammad acted on his own; however, it may never be possible to definitively determine why he chose to attack people on the UC Merced campus.”

Dorothy Leland, chancellor at UC Merced, said the university was relieved to finally have a resolution to this “very tragic event”. She continued, in a statement released on Thursday: “While I shared your desire for a quicker resolution, we are better served by law enforcement’s completion of its investigation in due course … Now, we move to the task of further healing and taking care of the needs of our students, staff and faculty.”