(AP) - Ferguson police Officer Darren Wilson did not receive a severance package when he resigned over the weekend, the St. Louis suburb's mayor said Sunday. Wilson, 28, won't receive any further pay or benefits, and he and the city have severed their ties, Mayor James Knowles told reporters a day after Wilson tendered his resignation, which was effective immediately. Wilson, who is white, had been on administrative leave since he killed Michael Brown, an unarmed black 18-year-old, during an Aug. 9 confrontation. He wrote in his resignation letter that his "continued employment may put the residents and police officers of the City of Ferguson at risk, which is a circumstance I cannot allow." His lawyer, Neil Bruntrager, told The Associated Press that Wilson decided to step aside after police Chief Tom Jackson told him about the alleged threats on Saturday. "The information we had was that there would be actions targeting the Ferguson (police) department or buildings in Ferguson related to the police department," Bruntrager said. He said Wilson, who had worked for the department for less than three years, and the city were already discussing an exit strategy, acknowledging that staying on as an officer there would be impossible. Many have criticized the authorities' handling of the case. When asked Sunday if there were any changes to Ferguson's leadership planned, Knowles said there were not. Many have called on Jackson to resign, but he told reporters he doesn't plan to do so. Earlier Sunday, Benjamin Crump, an attorney for Brown's family, said Wilson's resignation was not a surprise. "It was always believed that the police officer would do what was in his best interest, both personally and professionally," Crump said. We didn't believe that he would be able to be effective for the Ferguson community nor the Ferguson Police Department because of the tragic circumstances that claimed the life of Michael Brown Jr. Crump said the family is still considering civil litigation such as a wrongful death lawsuit, "but don't let that get confused with the fact that they really wanted the killer of their child to be held accountable." Wilson's resignation meant little to those protesting Saturday night outside police headquarters in Ferguson, where two people were arrested. Several shrugged their shoulders when asked what they thought, and protester Rick Campbell flatly said he didn't care about the resignation, noting: "I've been protesting out here since August." Victoria Rutherford, a resident who was not protesting, said she believed Wilson should have not only resigned, but been convicted of a crime. Wilson fatally shot Brown in the middle of a Ferguson street after the two scuffled inside Wilson's police SUV. Brown's body was left for more than four hours as police investigated and angry onlookers gathered. It isn't clear when that decision will be announced. It isn't clear what the future holds for Wilson, who has spent his adult life in police work and never wanted to do anything else, Bruntrager said. "In terms of what it (the resignation) means, it means at this point he doesn't have a paycheck," Bruntrager said. He has no income so he'll have to make some decisions pretty quickly.