A 74-year-old man was airlifted to a hospital with severe burns sustained in the Myrtle Avenue blaze, which broke out shortly before 5 p.m., responders said.
It was believed that his 72-year-old wife perished at the scene.
Two firefighters were taken to the hospital with injuries that didn't appear life-threatening, responders said.
The two-alarm blaze was declared under control around 6:30 p.m.
The Morris County Prosecutor's Office didn't disclose further information.
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