A 14-year-old boy who loves making clocks was arrested after a teacher noticed his pencil case was stuffed with electronic circuits.
Ahmed Mohamed, who also makes and repairs radios and regularly repairs his own go-kart, was brought in handcuffs to a juvenile detention centre.
Ahmed brought the clock into his school, MacArthur High School, Irving, Texas on Monday morning.
Police said they can still charge him with making a hoax bomb, although they acknowledge he told everyone who would listen that it is a clock, The Dallas Morning News reports.
The teenage boy has since been suspended from the school.
He created the clock on Sunday evening before he went to bed. It is comprised of a circuit board and a power supply which is wired to a digital display, all strapped together in a case with a tiger hologram on the front.
The clock was noticed when the alarm beeped in the middle of an English lesson.
Police spokesman James McLellan commented on the incident, saying: “We have no information that he claimed it was a bomb.
“He kept maintaining it was a clock, but there was no broader explanation.
“It could reasonably be mistaken as a device if left in a bathroom or under a car. The concern was, what was this thing built for? Do we take him into custody?”
The Council on American-Islamic Relations have taken note of the incident and have spoken to lawyers.