DALLAS (CBSDFW.COM) –  Investigators are searching for those responsible for two unrelated killings that happened in the early morning hours Sunday.

At 4 a.m., a police spokesman said Geoffrey Sowells, 25, and Terrance Robertson, 29, were drinking in a parking lot in the 9900 block of Whitehurst. Two men approached the two and tried to rob them.

During the scuffle, the suspects shot both men. Sowells died in the parking lot while Robertson was taken to Baylor and is currently stable. Investigators are searching for any witnesses.

Later in the morning, a homeowner left his house in the 2300 block of St. Frances at 5:45 a.m. and found a man shot on the sidewalk. The victim was taken to Baylor Hospital and died in surgery. His identity has not been released.

Dallas Police spokesman Kevin Janse said another witness heard a gunshot about ten minutes prior. Janse said authorities found a vehicle nearby with "evidence of the shooting inside." He did not say what that evidence was.

Police have no suspects in the case, and no eye witnesses have come forward.