The body of a young boy found over the weekend in southern Indiana was inside a hard suitcase, state police said on Tuesday.
The suitcase had a distinctive Las Vegas design on its front and back, Sgt Carey Huls said.
A Washington County resident looking for mushrooms found the body about 7.30pm on Saturday, police said. The body was in a heavily wooded area of eastern Washington County, Indiana.
A toll-free tip line for the case was established on Monday and has generated about 200 calls, but none of the calls have led to the boy's identity, Mr Huls said.
A post-mortem examination on the boy was conducted on Tuesday but no cause of death was determined, he said.
Based on information provided by the examination, investigators believe the child was about five years old, Mr Huls said.
He was earlier described as between 5 and 8 years old. He was black, about 1.2 metres tall, with a slender build and short haircut. He is believed to have died some time in the past week.