MANHATTAN BEACH, California — Police said Wednesday that they've identified someone they believe posted an ominous online warning that closed a Southern California school for two days.
Investigators believe the girl — who isn't a student in the district — made at least one of five anonymous postings on the website Yik Yak, Manhattan Beach Police Officer Stephanie Martin said.
One of the posts Monday urged students at Mira Costa High School to "watch out very closely at school today."
The postings prompted the high school to close Tuesday and Wednesday, but it's expected to reopen Thursday.
Martin told City News Service the girl has been interviewed but not arrested, and police were trying to determine if other people were involved.
There was no word on a motive.
A student spotted the first message and reported it to a teacher, Martin said.
Support for students and heightened security would await students Thursday when they return.
"Students can expect to have counselors available, to have an increased police presence on campus and to go back to high quality instruction in the classrooms," Superintendent Michael D. Matthews said in an email.