LEWISTON — Police Chief Brian O’Malley asked people for patience and support Tuesday as state police continued to investigate the death last week of Donald Giusti. In front of dozens of residents who converged on the council chambers to hear and respond to the briefing, O’Malley defended his department’s response to the recent violence, saying Lewiston police are working around the clock to bring the right people to justice, and are working to diffuse neighborhood tension. The City Council on Tuesday night approved an emergency ordinance to impose an earlier police curfew on Kennedy Park and to expand and upgrade camera surveillance in the downtown. Lewiston police are acting as support for the Maine State Police investigation, and O’Malley said the lack of information being released to the public is part of the effort to maintain an accurate investigation. O’Malley said it is a complex and unusual case because of the many teenagers and juveniles involved.