Three Brown University students are suing the school after they were injured in the December campus shooting, alleging that the university ignored warnings about a man who went on to kill two people and injure nine others at the school.

Three separate but nearly identical lawsuits filed last Thursday allege that a Brown University custodian saw the eventual shooter pacing the hallways of the Barus and Holley building multiple times before the shooting, behaving “in a manner he considered suspicious.” The custodian told campus security that he’d seen a man who appeared to be surveilling the building.

The lawsuits allege that Brown failed to take “reasonable and appropriate security measures” after the custodian’s report, failing to investigate the man’s “suspicious presence” or restrict access to the building.

On Dec. 13, a man identified as a 48-year-old former Brown student opened fire in Barus and Holley, which hosts Brown’s engineering school and physics department, killing 18-year-old MukhammadAziz Umurzokov and 19-year-old Ella Cook.

Two days later, he also shot and killed MIT professor Nuno Loureiro in Loureiro’s home in Massachusetts. The shooter was eventually found dead of a self-inflicted gunshot wound in a storage unit in New Hampshire.