CHICAGO — The head of the Chicago Police Department said Wednesday that his officers are now using high-tech strategies and equipment to fight crime, an announcement that came as the city’s police released statistics showing no letup in the death toll that captured the nation’s attention last year and sparked a Twitter warning last week from President Donald Trump.

Police Superintendent Eddie Johnson demonstrated how officers will use software to almost immediately learn when and where someone has fired a gun. At the news conference in a police district considered to be one of the city’s two most violent, Johnson also showed his audience a computer system that will help police predict where violence might erupt.

Chicago has been at the center of the debate about gun violence even before it finished last year with 762 homicides — a total higher than those of New York and Los Angeles combined. With a third of those killings occurring in one neighborhood on the South Side and one on the West Side, the department decided to open its first two Strategic Decision Support Centers in those neighborhoods.

“We are changing the crime-fighting culture within the Chicago Police Department,” Johnson said, adding that he believes the technology will lead to more arrests of violent criminals and thus a reduction in the number of homicides and shootings.

Johnson was set to announce the initiatives last week but had a dizzy spell at the news conference. He later explained that he had taken blood pressure medicine on an empty stomach.