As the trial for an NYPD sergeant accused of murdering a mentally ill woman in her Bronx apartment got underway Tuesday, the courtroom was filled with supporters from both sides.

The NYPD's Force Investigation Division is looking into how a Bronx man died just moments after he tried grabbing a gun from a responding cop during a brief run-in with authorities, police said.

A knife-wielding man was fatally shot by police after he threatened to stab his roommate in Bronx on Monday night, law enforcement sources said.