Police investigating small explosion near Mill Valley elementary school

MILL VALLEY, Calif. (BCN) - Police are investigating a small explosion that occurred in a secluded area behind a Mill Valley elementary school Saturday night.
At around 10:15 p.m., officers responded to multiple reports of a loud explosion heard near Edna Maguire Elementary School at 80 Lomita Drive, police said.
Officers however were unable to locate the source of the explosion as callers gave conflicting reports about where the explosion was heard, according to police.
This morning, at around 9:45 a.m., officers again responded to the school after a caller said they believed they had found remnants of the explosion.
Upon arrival, the caller led officers to a baseball field behind the school, where officers found a very small device, police said.
The area where the device was found was in a secluded area and a safe distance from the school's buildings.
Additionally, officers found no damage in the immediate area expect to the small device.
No injuries were reported, according to police.
Officers are continuing to investigate the incident.
Anyone who may have witnessed the explosion is asked to contact Mill Valley police at (415) 389-4100.