PITTSBURGH (AP) — An independent review panel has opened an investigation into the lack of a police presence despite a request for it at a Pittsburgh funeral where a shooting left six people injured last month.

Two shooters opened fire outside the Destiny of Faith Church on Oct. 28, wounding five people and causing a melee that injured a sixth person. The funeral was for a man killed two weeks earlier in a shootout between two neighborhood groups, police said.

Pittsburgh officials said no officers were present although a police presence had been requested. Acting Police Chief Thomas Stangrecki on Thursday vowed discipline for any officers involved, but it wasn’t immediately clear whether police failed to respond to the request or if they did respond and officers failed to show up.

Elizabeth Pittinger, executive director of the Citizens Police Review Board, said officers should have been there, request or no, “simply because of the assessment of intergroup tensions which is critically important to keep everyone safe.”

She cited other incidents — including gunfire at a youth football game in August where officials said promised officers never came — and asked whether supervision, communication or insubordination was to blame. Such questions, and whether deeper problems are indicated, prompted the review panel to open the inquiry, she said.

Shawn Davis, 19, of McKees Rocks and a 16-year-old Pittsburgh youth both face attempted homicide, aggravated assault and weapons charges in the Oct. 28 shooting at the funeral for 20-year-old John Hornezes Jr., who was among three people killed in an Oct. 15 shooting in Pittsburgh. Authorities have repeatedly declined comment on whether Davis and the teen suspect had any connection to Hornezes or anyone attending his service.