At least 15 people were injured Wednesday when two firetrucks responding to the same house fire collided near Los Angeles. Due to the impact, one of the vehicles ended up smashing into a restaurant.

The crash occurred in Monterey Park, Calif. shortly after 3 p.m. An Alhambra Fire Dept. truck collided with the Monterey Park fire engine at the intersection of Garfield and Emerson avenues causing it to plow into the Lu Dumpling House restaurant on the corner. Investigators say both vehicles had their lights and sirens on.

A mixture of firefighters, pedestrians and restaurant patrons are among the injured. One person is in crtical condition.

The person listed in critical condition was pinned between a fire truck and a table.

"All the employees in the back, they felt like (it was) an earthquake. It was very scary," said Vivian Lu, who works at Lu's Dumpling House. 

Another employee, who works at a floral shop across the street, was assisting a customer when she heard a loud boom.

"All of the customers ran outside," she said. "It was really bad. I hope everyone is OK."

Workers were able to stabilize most of the restaurant, preventing it from a total collapse. Beams had fallen due to the impact of the crash. By Thursday morning, most of the restaurant was boarded up.

It is unclear what caused the two vehicles to collide and the crash is under investigation. The California Highway Patrol's major accident team will lead the investigation which will look into the speed of the trucks and radio transmissions.

Alhambra Fire Chief Bill Walker said it's normal for the two departments to respond to the same fire. He also said that among the firefighters from his department that were injured, some had as little as one year experience, while others had over 20 years experience.