An 86-year-old retired doctor and Holocaust survivor died in a fire in his Long Island, home and smoking in bed may have been the cause, authorities said.

Adam Rufalowicz, of Hewlett, was found dead in a bathroom off his bedroom at 2:45 a.m. yesterday, said Nassau Fire Marshall Vincent McManus.

A neighbor said Rufalowicz had escaped Poland just before the Nazis invaded in 1939.