SAN MARINO, Calif. (KABC) -- The San Marino School District is taking steps for the first time to prepare for an active shooter with the hope they will never have to respond to such a crisis.
Wednesday, a mock drill simulated the advance of a lone gunman on the campus of more than 1,100 students.
"To witness people running through the hallways and people screaming and hearing fake gun shots, it brought the reality of the situation to us I think," said senior Erik Olson.
Some students found themselves pounding on classroom doors unable to get in because of the lockdown in place.
"If I was in the classroom I obviously wouldn't want anybody to come in but at the same time were in the hallway and helpless in the open and anyone could have hurt us," said senior Daphney Wang.
Students had been previously trained to exercise their best judgment.
"They were taught to run to a safe area or hide inside a secure room or last resort to fight," said San Marino Police Chief John Incontro.
Thoughts of the school shooting in Parkland, Florida were present in the minds of drill participants, though the San Marino exercise had been planned months earlier.
"When I saw like people like my age and my sister's age - we are so young and we shouldn't have to experience anything like that," Wang said.
Questions raised Wednesday included whether to install locks that could be shut remotely, how to better secure the campus perimeter and should officers respond with ballistic shields.
Police have a two-minute response time in San Marino, an upscale San Gabriel community of 13,000 people.
Neighboring police departments from Alhambra, South Pasadena and San Gabriel participated along with officials from other school districts.
"This is not something we want to do. It is what we have to do," said San Marino School Superintendent Alex Cherniss.
San Marino students learn to respond to active shooter in emergency drill