CORONADO, Calif. – Police swept the area near Coronado High School Tuesday afternoon after a bullet was found near the school’s football field, authorities said.

Police were called to the school around 10 a.m. after a student found a piece of a bullet outside of the field, Coronado Police Department officials said on social media. Police responded by increasing the presence of officers at the scene and at Coronado Middle School and Village Elementary School.

“There are no threats, and we are working in close collaboration with CUSD,” police said Tuesday.

In a later post, officials stated that gunpowder sniffing dogs were brought to the grounds and were also utilized in the search.

Classes were not stopped at any point during the day, according to police.

The matter remains under investigation at this time.