Tens of thousands of people were urged to evacuate as dozens of homes and buildings were engulfed in flames. Hundreds off natural gas specialist are being brought in to neighborhoods near Boston to inspect homes before thousands of residents an return home after an series of explosions on Thursday killed one person and injured more then 25 people.

“This will not be a simple process. And doing it right is essential to making sure everyone remains safe,” said Governor Charlie Baker on Friday morning.

Dozens of homes were engulfed in flames in the towns of Lawrence, North Andover, and surrounding communities about 30 miles north of central Boston. Massachusetts State Police tweeted that there were 70 different incidents in the area.

Leonel Rondon, 18, from Lawrence, was killed when an explosion caused a chimney to collapse on his car, according to the Essex County District Attorney’s office. He was rushed to Massachusetts General Hospital but died of his injuries around 8:30pm.

Though the cause of the fires was still under investigation Thursday evening, Andover Town Manager Andrew Flanagan said in an interview on CNN that “it’s our understanding that it has to do with gas pressure.” As many as 33,000 people in the town were urged to evacuate, and Flanagan said he had never seen any comparable situation.