A man who was months behind in his rent shot and killed his landlord and a police officer, then took an elderly neighbor hostage and barricaded himself in an apartment, authorities said. More than 50 police officers surrounded the wood-frame, two-flat residence on Chicago's North Side where the gunman was barricaded. A police negotiator was sent to talk with the gunman, described as "a huge male . . . 300 pounds, aged 50 to 55," said police Supt. Fred Rice.