Ossining schools were on high alert today after someone allegedly posted an online threat.

Ossining High School was placed in a lockdown and all other schools were placed in a lockout after school officials were alerted to a "non-specific" threat.

Emergency procedures were put into place at around 11:30 a.m., and police were stationed at district schools. The security measures were lifted at around 1:30 p.m. and regular dismissal procedures went into effect.

Police aren't releasing specific details, but say it was the second threat against the school in 12 hours.