Walter Colton Middle School was placed on lockdown, Tuesday afternoon, for about 30 minutes. In a message sent to parents obtained by KSBW, the Monterey Peninsula Unified School District (MPUSD) said they were notified by the Monterey Police Department that they needed to go into a lockdown. The lockdown was lifted 29 minutes after the first message. "The safety and well-being of our students and staff is our top priority," the message began. MPUSD did not know why police had asked the go into a lockdown. The Monterey Police Department has not responded to KSBW's requests for information. This is a developing story, stay with KSBW 8 for the latest.