BOSTON (AP) — The family of the 7-year-old boy who drowned at a Boston beach while attending a city-run summer camp has sued the city, camp supervisors and the mayor.

The suit filed Thursday by the parents of Kyzr (KYE'-zuhr) Willis alleges negligence for ignoring a state law requiring life jackets for children who are weak or non-swimmers. Willis drowned in July 2016 while attending a drop-in program at a community center overseen by the city.

The suit also alleges the program failed to provide enough lifeguards and counselors and failed to inform Kyzr's parents he would be near the ocean. It seeks unspecified damages.

Democratic Mayor Marty Walsh told the Boston Globe negotiations with the family are ongoing. He said Willis' death was "one of the saddest days" he's had as mayor.