It happened around 5:30 a.m. Thursday on the freeway southbound at Main Street.
Authorities told ABC13 the officer was in the fast lane, patrolling the freeway, when someone cut him off and swerved into his lane.
He tried to take evasive action, lost control and hit the retainer wall.
Officials say the officer hit the brakes on his motorcycle, and it began to vibrate. As a result, he released the bike and let it slide away from him, which is what officers are trained to do in that situation, said HPD Executive Assistant Chief Troy Finner.
Finner also said that other officers arrived quickly after the crash and along with an off-duty firefighter and a citizen, blocked the freeway to protect the officer, whose body ended up in another lane with cars driving around him.
The injured officer was wearing a helmet.
Police said initially that the officer's motorcycle hit road debris before being hit by an 18-wheeler.
"Don't ever underestimate the hearts of our citizens in this great city and our fire department and our police department. We've been through a few tough weeks as everybody knows, and when I received the call today, my heart dropped," Finner said. "Because I received the same thing that went out to y'all, that one of our officers had possibly been hit by an 18-wheeler."
The officer was taken to Memorial Hermann Hospital with a police escort. HPD tweeted that the officer is conscious and breathing. He's also in a lot of pain, but his spirits are good, Finner added.
Preliminary information is the officer's motorcycle struck road debris and an 18-wheeler then struck the motorcycle. All southbound lanes of the North Fwy are closed. Please use alternate routes if you're heading into the city from the north side. #hounews #houtraffic— Houston Police (@houstonpolice) February 7, 2019
HPD says the person who swerved into the officer's lane did not stop.
Out of respect for the officer, his name will not be released at this time, so he can contact his family about the crash.
The officer is a 10-year veteran of the force.
The freeway was shut down, but has since reopened.
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