Santa Monica College was locked down for about one hour Tuesday after school officials said they received a report of a gunman on campus.
College spokesman Bruce Smith said calls came in around 11 a.m.
The calls came from a woman and her daughter as well as a campus staffer so police took the issue very seriously and ordered the lockdown.
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After a search that involved officers on the ground and an aerial unit, officers said they found no evidence of a gunman. The lockdown was called off at about noon, according to Smith.
School is not in session but teachers and some incoming freshmen are on the campus, which is at 1900 Pico Blvd.
The locked down area included KCRW studios at Santa Monica College. Staffers were involved in a fund drive at the time of the lockdown.
Several staffers tweeted that they were allowed back to their buildings shortly after noon.
Smith said an email notification was sent to all employees.
Police concluded what the gunfire really was was a 22 caliber nail gun being used on the upper floors of a construction project on campus.
The nail guns were being used to drive nails into large concrete," said Santa Monica Police Sgt. Richard Lewis.
He said the sound of that makes a cracking noise which the witnesses mistook for gun shots.
Police said the good news from this exercise is that the email alert system on campus actually worked.
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