Published: May 14, 2011 7:57 PM EDT
Updated: May 14, 2011 4:58 PM EDT

MIAMI, Fla. (AP) - Authorities say a Miami-Dade police officer fatally shot a mentally ill man during an altercation.
 
Police say the officer, who has not been named, was patrolling the North Miami Beach area Friday afternoon. When he approached 34-year-old Manuel Bueno, police say Bueno flashed a knife. A police spokesman says the officer responded with lethal force.
 
Bueno's grandmother, 81-year-old Angela Vasquez, says Bueno has battled mental health issues since being diagnosed with HIV 10 years ago, but he wasn't typically a violent person.