Scott Ryan was able to keep the gunman from forcing his way through a door at his 301 Victory Ave. apartment, and then ran out the back door, police said. The incident occurred at approximately 4:45 a.m.
He struggled and then closed the door," Police Lt. Peter Frisoni said.
Ryan, a 20-year-old who moved into the apartment Saturday, ran to a friend's house on nearby Chestnut Street and called police.
Minutes later, the Victory Avenue house erupted in flames.
Fire Chief Robert Farstad said the fire, which appears to have begun in Ryan's rear apartment, was set. Farstad declined to speculate about why.
"What he is telling us is possible and believable," Frisoni said of Ryan. "Things like what happened to him do happen here."
Building owner Carmen J. Seecharran and her uncle, who live in the second-floor flat, were able to escape uninjured, the chief said. Ryan lived alone. The front, first-floor apartment was vacant.
Farstad said that when firetrucks arrived, the flames had already spread throughout much of the house, and the roof quickly caved in.
"We had to evacuate the whole building," he said.
It took firefighters approximately 90 minutes to extinguish the flames. The first-floor apartments and the attic were gutted, he said. The second-story apartment also was damaged, though not as badly.