The NYPD has arrested and identified a 29-year-old man in connection to the death of a 3-year-old boy in East Flatbush.

Police say Kevin James, 29, was arrested Tuesday. Police believe James is not related to child. James has been charged with murder and assault.

One downstairs neighbor is mourning the loss of three-year-old Denim Brown, but also says she's unsettled because she interacted with James in the past.

"I've had problems with them but I never thought he could do something like that," said Carmen Deloach, the downstairs neighbor to where Denim Brown was found dead. "His brother came here and argued with me, what if they attacked me? I never worried about that with Kevin though."

Police sources tell News 12 that the three-year-old was left with a family friend and left in a bathtub in the apartment where he was found dead.

Tenants created a vigil in the lobby of the building, lined with toys and candles in the common area. The walls are covered with the smiling face of Denim Brown.

The cause of the boy's death has yet to be determined and police have not said any leads on what the motive could have been to cause this death.