NEWARK, N.J. (CBSNewYork/AP) — Crews in Newark were removing huge mounds of trash Tuesday, after they were dumped at the site of a memorial set up in honor of six family members killed in a fire this summer.

City officials as of Tuesday were still trying to determine where the trash came from.

The Rev. James Johnson, the pastor of church next to the home on South 15th Street, told News 12 New Jersey on Tuesday that he noticed the garbage piling up two weeks ago, when the city demolished what was left of the house where the fire broke out.

The memorial had been placed at the site shortly after the fire occurred on Father’s Day.

Johnson believes someone is illegally dumping the trash during the overnight hours, but an investigation is ongoing.

The blaze ripped through one home and killed six members of one family, spread to another home and went on to destroy both structures.

Salome Stewart and her husband, Reginald Stewart, both 58, were killed in the fire, along with Salome Stewart’s sister, 47-year-old Natasha Kinsale, who all lived in the house.

Three visiting family members – Noreen “Michelle” Johnson and her son, Stephon Sydney, 15, of Crawford, Georgia; and 11-year-old Zion Forbes, of East Orange, also died.

Authorities have said the bright, plastic flowers the family used to decorate the front of the home acted as an accelerant in the fast-moving blaze.

The victims were found in their pajamas on the upper floors of the single family home, which was reduced to a charred frame, with stray plastic blossoms and strands of plastic vines twisted around fire-damaged wreckage.

Complaints mounted after the blaze about response times by the Newark Fire Department, amid frantic calls for help.

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