Lock-downs and evacuations in seven states followed Campus bomb scares and perceived threats, a day after a Virginia Tech student's shooting rampage killed 33 people.
One threat in Louisiana directly mentioned the massacre in Virginia, while others were reports of suspicious activity in Texas, Oklahoma, Tennessee, North Dakota, South Dakota and Michigan.
In Louisiana, parents picked up hundreds of students from a high school and middle school amid reports that a man had been arrested Tuesday morning for threatening a mass killing in a note that alluded to the murders.
Bogalusa Schools Superintendent Jerry Payne said both schools were locked down and police arrested a 53-year-old man who allegedly made the threat in a note he gave to a student headed to one of the schools.
"The note referred to what happened at Virginia Tech," Payne said. "It said something like, 'If you think that was bad, then you haven't seen anything yet."
In Rapid City, South Dakota, schools were locked down after receiving reports of a man with a gun in a parking lot at a high school. No shots were fired and no injuries were reported, police said.
In Austin, Texas, authorities evacuated buildings at St. Edward's University after a threatening note was found, a school official said.
University spokeswoman Mischelle Amador declined to say where the note was found and said its contents were "nonspecific."
Seven North Dakota State University buildings were evacuated after a duffel bag was found outside a bus shelter in the main part of the campus. NDSU spokesman Dave Wahlberg said the shootings in Virginia reinforced the need to "err on the side of safety."
In Bloomfield Hills, Michigan, police attributed a 30-minute lockdown at a school complex in response to jittery nerves following the Virginia slayings.
School officials called police after parents and students reported spotting a tall man in a skirt, high heels, lipstick and a blond wig near a school drop-off area, Lt. Paul Myszenski said. Police were unable to find anyone meeting the man's description.
At the University of Tennessee at Chattanooga, officials ordered three campus administration buildings evacuated for almost two hours Tuesday morning in response to a telephone bomb threat. The city's bomb squad searched the buildings but found nothing, campus spokesman Chuck Cantrell said.
Cantrell said there was no reason to believe the bogus threat was related to the shootings at Virginia Tech, but "we just chose to err on the side of caution today."
At the University of Oklahoma, a man was spotted on campus carrying a suspicious object, officials said.
The man was carrying an umbrella, not a weapon, and he later identified himself to authorities, University of Oklahoma President David Boren said in a statement.
"We now consider the matter closed," Boren said. "We always want to err on the side of caution in a situation like this."
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