Ahmed Mohamed: Texas police knew he didn't have a bomb but arrested him anyway

Police Chief Larry Boyd said they thought it was a 'hoax bomb' designed to scare the school

Ahmed Mohamed was arrested after his homemade clock was mistaken for a bomb (Ben Torres/Getty Images)

It turns out that the Texas police officers who this week arrested 14-year-old Ahmed Mohamed knew his homemade clock was not a bomb.

Speaking to MSNBC, Irving Police Chief Larry Boyd said "the officers pretty quickly determined that they weren't investigating an explosive device" and that the arrest was made over the prospect that it was a 'hoax bomb' intended to scare people at the school — "something that is not really a bomb, but is designed and presented in a way that it creates people to be afraid."

Host Chris Hayes, who pointed out that no bomb squad was called to the scene and that the school was not evacuated, asked: "But he never called it a bomb, right? He just kept calling it a clock. I mean, it never came out of his lips, he never did something or started showing it around saying 'Look at this bomb I have.'"

Boyd responded: "There definitely was some confusion and some level of information that didn't come out immediately."

Irving police chief: police knew 'pretty quickly' homemade clock wasn't a bomb

Mohamed, a science enthusiast who dreams of attending the Massachusetts Institute of Technology, was marched out of MacArthur High School in handcuffs on Monday after school officials called the police.

He told reporters he was "very sad" his teacher thought his clock was a weapon: "I built a clock to impress my teacher but when I showed it to her she thought it was a threat to her. I'm very sad that she got the wrong impression of it."

Ahmed has since said he intends to leave the school.

In the interview, Boyd also refused to admit Irving police had made a mistake in detaining Ahmed.

"The officers made the decision they did with the information they had with what they thought was right at the time. We are clearly going to review this. We want to always look at ways we can enhance and have a better outcome."

Irving Mayor Beth Van Duyne, who backs a state ban on Sharia law, has also defended the decision to take the teenager into custody.

The arrest has been widely criticised, with top US scientists telling Ahmed not to lose his passion for invention.

And President Barack Obama this week invited him to the White House, tweeting: "Cool clock, Ahmed. Want to bring it to the White House? We should inspire more kids like you to like science. It's what makes America great."