On Nov. 4, 2015, Faisal Mohammad was shot and killed for stabbing four individuals on the University of California-Merced campus. An FBI investigation later discovered pro-ISIS propaganda in Mohammad’s possession. This has been added as the 77th Islamist-inspired terror attacks or plots on U.S. domestic soil since Sept. 11, 2001, which brings the total number to 84. The U.S. must remain vigilant as the threat of Islamist-inspired terror remains a concern.

According to reports, Mohammad apparently committed the act after being kicked out of a study group. The FBI’s statement declared that “the incident occurred without warning or advance indication.” The 18-year-old first attacked and wounded one student, then proceeded to stab three others before being shot and killed by the police. A later report revealed that his backpack contained a photocopy of an ISIS flag in addition to zip ties, a knife, glass breaker, and list of specific plot details, which included taking hostages and killing students and police officers.

The press release stated that Mohammad had visited ISIS websites in the few weeks just before the attack and that his laptop “contained pro-ISIS propaganda.” And though the investigation is still on-going, the FBI has concluded Mohammed may have been self-radicalized as no direct connection with ISIS has been found.

The Heritage Foundation has kept track of all the publicly known Islamist-inspired terrorist attacks and plots since 9/11 through an interactive timeline. This will bring the record number of Islamist-inspired attacks or plots in 2015 up to 16. It will also be the 73rd out of 84 attacks or plots which have been home-grown. There have already been three Islamist-inspired attacks or plots this year.

The FBI will continue its investigations to figure out whether or not Mohammad was directly affiliated with ISIS. In light of the rising number of terror attacks on U.S. soil, Congress should maintain a proactive approach to preventing terrorism before it strikes.