Thousands of residents fled a city in northern California on Wednesday as a series of fast-moving fires spread overnight, burning dozens of homes and structures.

The fire outside Vacaville, a city of about 100,000 residents located near the state capital Sacramento, is part of a series of blazes that have scorched nearly 50,000 acres (20,200 hectares) in northern California in recent days.

Taking to Twitter, Vacaville police said, “If you’re asked to evacuate, please do so SAFELY”.

“Practically every single first responder unit in town is actively working to safely notify, evacuate and fight the fires, so our residents are safe”, he further added.

Most of the people suffered burns as they ran for their lives.

According to the fire officials,the blaze was zero percent contained in the early hours on Wednesday and threatened some 1,900 structures in the area.

The group of fires — known collectively as the LNU Lightning Complex and taking place as the state faces a torrid heat wave — has so far destroyed dozens of buildings or structures in three counties.

Governor Gavin Newsom has declared a state of emergency to facilitate the release of emergency funds.

“We are deploying every resource available to keep communities safe as California battles fires across the state during these extreme conditions,” Newsom said.

Firefighters said that in total, some 30 fires across the state had torched some 120,000 acres.

The wildfires are spreading largely uncontrolled and have intensified because of the record-breaking heat.

In the past week, California’s Death Valley has been experiencing historic high temperatures, with the mercury rising as high as 130 degrees Fahrenheit (54.4 degrees Celsius).

Nearly 45 million people across the western United States were under an excessive heat warning or heat advisory Wednesday.

The scorching temperatures have put a massive strain on the state’s power network, with blackouts leaving some 30,000 people without service, according to Power outage.us.

In 2018, of the 44 people killed, 42 died in Northern California’s Camp Fire, while two others were killed in the Woolsey Fire in Malibu.

The fire came amid red flag warnings issued for some areas in Southern California due to extreme wildfire risk.

(With inputs from agency)