According to witnesses, a family had gathered to celebrate the life of a relative who had recently died when the shooting occurred on Thursday.
Emergency services responded to calls that an incident had taken place on Midland Avenue, firefighters say.
Ambulances were seen leaving the scene at about 21:15 (01:15 GMT).
Police later said the shots had come from across the street, hitting the lawn where the victims had gathered for a memorial, US media report.
Details of the victims, reportedly aged from eight to 35 years, have not yet been released. None of the injuries sustained are said to be life-threatening.
Footage posted on social media showed an area of the street cordoned off with police cars and officers lining the road as residents gathered.
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