STOCKTON (CBS13) – A fire truck crashed with another car en-route to a call, causing the back cab of the truck to crash into a building. The impact injured a firefighter who was steering the back end of the truck at the time.

There were terrifying moments Outside Riggs Real Estate in Stockton early Monday morning.

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Just after 2 a.m., the fire truck hit a car and the tiller on the truck’s trailer — with the tiller driver inside — crashed into the office.

“People came out right away to secure the building,” said Theresa Dread with Riggs Real Estate.

Four Stockton firefighters were headed to a call on Solano. The crew was coming from Station 4, less than a two-minute drive from where the crash happened. It’s not clear whether the sirens were on at the time.

Dread showed CBS13 the office surveillance footage that captured the moment of impact, just out of view.

You can make out the bright flashing lights of the fire truck and the dust flying. Employees at the juice bar next door arrived to work to see this mess.

“It’s just crazy, it kind of breaks my heart. Poor guy is at work trying to help someone else and that happens,” one employee said.

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The tiller truck is specifically designed for making tight corners, especially in the city. The driver sits in the back and steers.

The injured firefighter posted a message to his colleagues on Stockton Firefighters’ social media pages:

“Hey, I’m doing good…but it could have been a lot worse! Surgery in a few hours. Don’t need anything now but I’ll let you know. Thank you for checking on me! Love you guys.”

The firefighter suffered a broken femur and bruised spleen.

Dread says the business plans to rebuild.

“We will just keep on going,” said Dread.

The driver of the other car was taken to the hospital and released.

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Stockton police are going to investigate how this crash happened and who was at fault.