A "homemade explosive device" was detonated at around 10 p.m. Wednesday in a grass field directly behind La Entrada Middle School at 2200 Sharon Road in Menlo Park, Sgt. William A. Dixon of the Menlo Park Police Department reported.
"There were no reported injuries or substantial property damage resulting from the detonation of the device," Sgt. Dixon said in a statement.
A 17-year-old juvenile, a resident of unincorporated Menlo Park, admitted to detonating the device in the grass field, police said. The juvenile, whose name was not released, was charged with possession and detonation of an explosive device.
Police and the San Mateo County Sheriff's Office bomb squad searched the juvenile's home and found no other explosive devices or materials used to make such devices, police said.
Police said that at around 10:09 p.m. Wednesday (June 16) they received multiple reports of a loud explosion in the Sharon Heights neighborhood. The residents and witnesses said the noise appeared to come from La Entrada Middle School.
The San Mateo County Crime Laboratory helped gather evidence at the scene.
Police ask anyone with information about this incident to call Officer Swanson at 330-6300 or the anonymous tip line, 330-6395.