That suspect was identified by police on Monday as 23-year-old Daniel M. Santucci Jr. of the 600 block of New Road in Wilmington.
Investigators say Santucci lured the child into his car from Sugar Plum Court in Pike Creek back on April 6.
Police allege he kidnapped her, sexually assaulted her, then threw her into a large pond in Wilmington's Banning Park.
The child was found by a good Samaritan, who discovered the child walking alone and barely clothed. Police say that person comforted the girl until help arrived.
Santucci had been identified as a person of interest in the case, police say, and during the investigation police found his black Honda Civic abandoned in the middle of Centerville Road with the driver's side door open.
Police believe Santucci staged his disappearance, then fled to Florida on a Greyhound bus.
Santucci was located and arrested on April 20, and was held in Florida until he was extradited to Delaware on May 1.
Santucci is charged with first-degree attempted murder, first-degree kidnapping, unlawful sexual contact with a person under 13 and possession of child pornography.
That child pornography was not of the victim, police say.
He is being held on more than $1 million cash-only bail.
News of the arrest broke on Sunday, and it had residents breathing a sigh of relief.
"Thank God, I just thank God that he's been caught," said resident Pat Weaverling.
It's also welcome news for 11-year-old Kal-kidan Endashaw, who was playing with the victim in their neighborhood when she was snatched.
"I saw a car slow down over here. And my friend was like 'is he telling them to come in the car?'" Endashaw recalled.
With her father by her side, Endashaw gave Action News a firsthand account of the terrifying seconds after the abduction.
"I said 'Excuse me, what are you doing?' Then I saw him grab her and start driving down, and then I started running and screaming. And I started yelling for help," she said.
Trying to chase after the car, the 11-year-old was no match for the suspect's dark colored sedan with tinted windows.
He makes off with the 4-year-old, who hours later, is discovered barely clothed and walking alone in a nearby park.
"The kids haven't been playing outside anymore. The street used to be full of kids, and everybody is on alert," said Weaverling.
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