Alden schools were in lockdown for roughly an hour Thursday afternoon, the Erie County Sheriff's Office said.
At about 2 p.m., Alden High School administrators "received information that could potentially endanger the welfare of our high school students and faculty," the district said in a news release.
Deputies responded to an incident that was reported to the school resource officer, the Sheriff's Office said.
Law enforcement deemed the situation safe at about 3 p.m. and told the district "there was never any imminent danger," school officials said.
Deputies were clearing the scene and the lockout was lifted, the Sheriff's Office tweeted at 3:21 p.m.
Officials have not released any further details on what triggered the lockdown but said the situation remains under investigation.
All evening activities in the district will go on as scheduled, the district said.