NORTH PORT — After thoroughly searching North Port High School for explosives this week, police say there were no bombs — only a hoax that created hysteria and hundreds of absences over a two-day period.

On Monday, police were alerted to a “anonymous group” Facebook posting that may have reached 4,100 followers, threatening there would be explosives in bathrooms and lockers on Tuesday. The posting said the school would go up in a ball of flames. The individual either hacked into a memorial page for Marcus Alan Freeman, 16, who died in a crash on Interstate 75 in 2011; or set up a new page using Marcus’ name. After seeing the post, hundreds of students called their parents and were picked up from school. Many didn’t return again Tuesday.