Thanks to a tip from a citizen, DeKalb County police have identified a suspect in the hit-and-run death of a 2-year-old boy.

Concepcion Cruz, 57, a resident alien from El Salvador, is the man police are searching for, DeKalb Police Chief Cedric Alexander said Thursday.

"We are looking for this gentleman and we are asking the community to help us," he said.

Homeland Security is involved in the case and Cruz will be placed on no-fly list, Alexander said.

Cruz's truck was found in Gwinnett County on Wednesday, he said, and a search warrant and arrest warrants are being prepared.

Caleb Lindsay, 2, and his 4-year-old sister, Meyaria, were standing at the entrance of a Tucker Walmart on Saturday afternoon with their mother waiting to cross the road when they were struck by a white pickup truck, police said. They were taken to Children's Healthcare of Atlanta at Scottish Rite, where Caleb died. Their mother, Vashti Lindsay of Tucker, was not injured.

A witness told investigators that the hit-and-run driver drove up on the curb and struck the children, stopped a few feet away, threw a beer bottle out of the window and left the scene, according to the incident report.

Cruz visits the metro Atlanta area frequently and is thought to have family here, Alexander said. He travels back and forth to El Salvador.

His family last saw him recently, and then "he went ghost on us," according to the chief.

"He may be out of state, he may still be in the metro area, he may be on his way back to El Salvador," Alexander said.