At 2:53 p.m., the Alameda Police Department received a call from a witness reporting that two men were arguing near the Alameda Main Library. At this time, APD was unaware of the incident at the high school. At 3:05 p.m.,
dispatchers were told that one of the men was a teacher and he was following the other man after an on-campus incident. After receiving this information, officers immediately responded to Alameda High School. At 3:21 p.m., the teacher then contacted APD to report that he lost sight of the person in Oakland.