The mob had Cyrus killed.
The Warriors, Streets of Fire and possibly Last Man Standing all take place in the same world, at different times.it's more or less the "Walter Hill verse"
The Warriors is a prequel to Escape from New York
Luther is an undercover cop who has Become The Mask.His assignment was to infiltrate the gangs and take down Cyrus. He tipped off the cops to the meeting. However, he was in so long that he became psychotic.