PATERSON — A fire early Tuesday morning that spread to four buildings displaced 44 people from their homes and sent five firefighters to the hospital.

Flames broke out in a home on Summer Street in Paterson around 1:30 a.m., Paterson Fire Department Chief Brian McDermott told reporters at the scene, and spread to  adjacent homes, completely destroying three of them.

McDermott said the heat and humidity played a role in firefighting efforts, as three firefighters were hospitalized for heat exhaustion. A captain and battalion chief were injured in the fire, according to the chief.

WPG Chief Meteorologist Dan Zarrow said a humid air mass prevents sweat from evaporating, making the human body unable to naturally cool itself, potentially a very hazardous situation.

McDermott said a cause of the fire remained under investigation.