By Lauren DiSpirito

GOLDEN, Colo. (CBS4)– The Colorado State Patrol investigated a serious crash between two sedans and a semi-truck in the eastbound lanes of Interstate 70 at Colfax Avenue on Wednesday afternoon.

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Emergency responders rushed to the crash at mile marker 261 just before 2:30 p.m. Wednesday. Five people were rushed to the hospital including two children who were seriously injured. The children were flown to Children’s Hospital in Aurora.

All eastbound lanes of I-70 were blocked for several hours. Drivers were urged to find alternate routes because of delays in the area due to the crash investigation and cleanup. By 6 p.m. traffic was able to get through in one right hand lane.

Copter4 flew over the crash scene at I-70 and Colfax Avenue (credit: CBS)

Copter4 flew over the crash scene at I-70 and Colfax Avenue (credit: CBS)

The crash happened in an active construction zone where cones started tapering traffic down to just the middle and right lanes past C-470.

Colorado State Trooper Nate Reid said the driver of the semi-truck, Carlos Monroy, 60, of Aurora, was traveling in the middle lane when traffic slowed and he was unable to stop. Monroy’s vehicle struck a white Chevy Malibu from behind, spinning the vehicle into the closed left lane, then struck a second vehicle, a Toyota Yaris, before coming to a stop.

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A family of four from Florida was driving in the Chevy Malibu, two adults, both age 40, were taken to St. Anthony’s Hospital and treated for their injuries and released. The two children who were riding in the car’s back seat were seriously hurt. At the time of the crash, the children were properly restrained in booster seats, according to Reid.

The female driver of the Toyota Yaris was transported to St. Anthony’s Hospital with what Trooper Reid described as “moderate” injuries.

What caused the crash is being investigated. Troopers do not know whether speed was a factor but did indicate that the 65 mph speed limit in the area had been reduced to 55 mph through the construction zone.

Copter4 flew over the crash scene at I-70 and Colfax Avenue (credit: CBS)

Copter4 flew over the crash scene at I-70 and Colfax Avenue (credit: CBS)

“The semi is a big vehicle,” Reid said, “we’re not sure if he was distracted at this point or what.”

Reid says troopers are investigating the semi-truck for possible defects and what traffic patterns were like inside the construction zone at the time of the crash. He says the crash is a reminder to all drivers to be vigilant.

Copter4 flew over the crash scene at I-70 and Colfax Avenue (credit: CBS)

Copter4 flew over the crash scene at I-70 and Colfax Avenue (credit: CBS)

“Whatever distractions they have in their world, they need to put those aside,” Reid said, “Even more so when you see cones and lane closures, this obviously could have been avoided there’s six lives in this whole thing that could have been changed.”

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Lauren DiSpirito is CBS4’s Northern Newsroom reporter. Follow her on Twitter @CBS4Lauren. Share your story ideas with her here.