The blaze broke out at a home on Vista Drive at 10:21 p.m., prompting a response from the Jericho Fire Department and several other area fire departments, according to detectives from the Arson Bomb Squad.
The fire heavily damaged the home and spread to neighboring attached residences, police said.
Two firefighters were injured during the response, officials added. One suffered an ankle injury and was taken to a local hospital, while the other experienced difficulty breathing and was also hospitalized.
The Nassau County Fire Marshal and the Arson Bomb Squad were called to the scene to investigate.
The cause of the fire is under investigation.
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