One person is dead after a house fire in Simi Valley, which authorities determined to be caused by explosions from fireworks on Thursday afternoon.

The said they received calls around 11:48 a.m. about a possible explosion that could have been caused by fireworks on the 1600 block of Edmund Street. It was later confirmed by VCFD that the explosions were from fireworks.

"It was a huge explosion," neighbor Andrea Cardona said. "This house rocked. It sounded like a sonic boom, like a rocket ship was coming in."

When firefighters arrived, they quickly took a "defensive posture" and upgraded the fire to a 2-alarm. Officials said the fire in the garage extended into the attic and other parts of the home. 

"The roof collapsed on the garage," VCFD spokesperson Scott Thomsen said. "The garage door pieces of it were blown to the front street on the neighbor's house."

The is asking people to avoid the area of Fitzgerald Road between Hudspeth Avenue and Gibson Avenue until further notice.

This incident remains under investigation. 

"If it was fireworks that caused this, then you can see the dangers of letting off any fireworks," Cardona said. 

Neighbors said that the man found inside the home was in his 40s and lived in the house with his mother. She was at work when the explosion happened.