SAN JOSE (CBS SF) — Hundreds of students have been released early as police investigate a report of possible shots heard Wednesday morning behind a school that went under a partial lockdown in San Jose bordering Morgan Hill, police and school officials said.

Around 9:30 a.m., officers responded to a secondhand report of shots heard near a school in the 9500 block of Monterey Road that falls within San Jose city limits, police said.

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Charter School of Morgan Hill at 9530 Monterey Road has been on semi-lockdown since about 9:45 a.m., principal Paige Cisewski said.

School staff members heard sounds of firecrackers or shots nearby and alerted police, Cisewski said.

Students were allowed to go outside of the classroom to use the bathroom or grab their lunch, but recess and physical education classes were held indoors, she said.

The campus serves about 640 students in kindergarten through eighth grade, according to Cisewski.

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The school remained under semi-lockdown through the morning and began to dismiss students around 1:30 p.m., ahead of their regularly scheduled 2:45 p.m. dismissal, school receptionist Nancy DePalma said.

School officials decided to end the day earlier to relieve congestion next to the school where police remain on scene, DePalma said.

Parents have been notified of where to pick up their children, according to DePalma.

No injuries were reported, police said.

Officers are searching the area and investigating the report but the incident hasn’t risen to an active shooter situation, according to police.

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