CLAREMONT (CBSLA) – High school and college athletic programs across the country have been forced to transition to online workout programs amid the coronavirus pandemic, and this has left some of them vulnerable to security issues.

Claremont High School’s head football coach reported Tuesday night that his team’s first virtual practice of the spring was “zoombombed” by uninvited visitors.

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“Coaches please be careful when using Zoom,” head coach Shane Hile tweeted. “Today we had our first Spring “practice” using Zoom and we were ‘Zoom bombed.’ Unfortunately our players and staff saw some inappropriate images.”

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With videoconferencing for schools and businesses becoming commonplace, zoombombing – in which uninvited people hack a Zoom conference and post explicit content — has become a major issue.

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Earlier this month, Zoom founder Eric Yuan addressed the issue, admitting there were security flaws. For information about how to ensure your Zoom conference is more secure, click here.