The accident happened around 8am on the North Sam Houston Tollway at Mesa Road. Those lanes remain closed as the investigation continues.
According to officials, Deputy Jason Denham, a 10-year veteran of the sheriff's department, was headed westbound when traffic came to a standstill. He wasn't able to stop in time and ended up slamming into the back of a black SUV.
Deputy Denham was unconscious and transported to the hospital in critical condition. As rescuers attempted to free Deputy Denham, his K-9 officer, Sjors, wouldn't allow it. Other K-9 officers were called to scene to assist with the police dog, but Harris County Sheriff Adrian Garcia says the dog did not hinder the rescue efforts.
Life Flight took the injured deputy to the hospital where he underwent surgery.
"His condition is critical. He has received severe trauma to the left side of his body. He's got a long road to recovery ahead of him, but doctors are hopeful," Garcia said.
The K-9 officer was checked out by a vet, but appeared to be OK.
Two people in the SUV were taken by ground to Memorial Hermann Hospital and three others were taken to nearby hospitals for their injuries.
A third driver in a Kia was also involved in the accident, but didn't appear to be injured.
The focus now is on Deputy Denham and his recovery and reuniting him with his K-9.
"Our prayers and hearts are with the family. We also understand K Sjors is OK, and I'm sure he's anxious to get back with his partner," said Liz Lara Carreno, executive director of K9s 4 Cops.
Garcia said Denham's wife of about 15 years is at the hospital with him.
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