More than 100 firefighters are working to control the fire that erupted at about 10:15 p.m. Sunday at the Windsor at Harper's Crossing complex.
The Philadelphia Inquirer reports ( http://bit.ly/NCqbDl) that a spokeswoman at St. Mary Medical Center in Langhorne says three firefighters are being treated there. Their conditions were not immediately available.
The American Red Cross tweeted that it is assisting more than 20 residents who've been displaced.
Information from: The Philadelphia Inquirer, http://www.philly.com