Pregnant Woman, 25, and Man Who Recently Celebrated His 20th Wedding Anniversary Killed in Mo. Crash

Facebook (2) Kaitlyn Anderson and James Brooks

A pregnant mom-to-be and a man who had recently celebrated his 20th wedding anniversary were tragically killed on Thursday after they were struck by a car while performing road work.

In a press release on their website, the Missouri Department of Transportation (MoDOT) identified the two victims as employees James Brooks, 58, and Kaitlyn Anderson, 25.

MoDOT officials said Brooks, Anderson and a third employee were struck by a vehicle while they were working on striping operations on a road in St. Louis over Interstate 255.

A traffic crash report released by the Missouri State Highway Patrol noted that the trio was standing behind a Chevrolet Silverado that was stopped with its emergency lights on for mobile construction work around 11 a.m. when the crash happened.

A Chevrolet Cavalier, driven by Stanley McFadden, 52, of Hillsboro, Missouri, hit the Silverado and three workers after he drove through the construction zone, according to the report.

Brooks and Anderson died at the scene from their injuries, while the third employee — identified as Michael Brown, 35 — suffered "serious" injuries and was transported to a nearby hospital, the report stated. McFadden was also transported to the hospital with "moderate" injuries, per the report.

At this time, Brown and McFadden's conditions are not known.

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"Our hearts are breaking and our sympathies go out to all the families of our employees," Tom Blair, the MoDOT St. Louis District Engineer, said in a statement. "These are our friends and coworkers and their presence will be sorely missed by us."

"The Patrol sends its condolences to MoDOT after the tragic loss of Kaitlyn Anderson and James Brooks today. Our thoughts are with their families during this difficult time," the Missouri State Highway Patrol Colonel added in a tweet. "Wishing a speedy recovery to the third MoDOT employee that was injured."

According to MoDOT, Anderson was an intermediate maintenance worker who had worked for the department for two years.

Her obituary states that she was five months pregnant at the time of the crash.

"Kaitlyn had a heart of gold," her mother, Tonya Musskopf, told CBS affiliate KCTV. "She was honest and caring and would do anything for anybody."

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In a Facebook post, Anderson's aunt, Tabitha Moore, said of the tragedy: "We are in shock and our hearts are shattered. To my beautiful niece, my first baby girl, my best friend: I love you so much. There are no words to describe our bond and my love for you. My heart isn't ready to accept what my brain is telling me."

"Thank you for always being there for me and my kids. You were their fiercest protector and defender and my closest friend," Moore continued. "The same way you loved them I love you. I am so thankful to have had you living with us and being such a huge part of our lives... To say you will be missed is grossly understated. I can't even find the words to say what my heart feels so I'll just say I love you bigger than the sky."

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In their release, MoDOT stated that Brooks was a senior maintenance worker who had worked for the department for almost nine years.

Family members told KCTV that he was the father of eight children and he and his wife had just celebrated their 20th wedding anniversary in October.

"Very, very outgoing, extroverted... Just a great person," cousin Bishop Ike Motley told the outlet. "Once you met James, you never forgot James."

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Officials say it is unclear what caused the accident, according to KCTV.

"It's scary to think these MoDOT workers are out here doing their job like any other normal day with no idea something like this would happen," Cpl. Dallas Thompson with the Missouri State Highway Patrol told the outlet. "At this point in time, we can't speculate on what caused it as far as speed or what not."

Speaking to ABC/CBS-affiliate KTVO, Thompson added that Missouri law requires drivers to change lanes when approaching transportation department vehicles, so long as it's safe to do so.

"We are still investigating what happened here," he told KTVO. "But people need to move over and eliminate distractions to keep people out here just doing their jobs out of danger."