Claims of an active shooter at several Inland Empire high schools made Tuesday morning are false, police officials said.

Rancho Cucamonga Police Department officers responded to reports of an active shooter at Alta Loma middle and high schools around 8:45 a.m., but upon arrival, no evidence of a shooting was found.

Similar calls made to San Andreas High School in San Bernardino, Chaffee High School in Ontario, Upland and Montclair high schools were also hoaxes, San Bernardino County Sheriff’s Department spokesperson Gloria Huerta said.

An investigation into the reports is ongoing, and no further details have been released.

In Los Angeles County, sheriff’s officials responded to an active shooter call at Duarte High School and California School of the Arts – San Gabriel Valley.

Both schools were placed on lockdown and deputies investigated, but no active shooter or threat was found, city officials said.

“Schools in the area have been receiving a series of these ‘prank’ calls for the last two weeks,” officials said in a news release without elaborating.

KTLA’s Sofia Pop Perez contributed to this report.