(KANSAS CITY, Mo.) -- Investigators want the parents of missing 11-month-old Lisa Irwin to submit to separate interviews and answer a list of "tough questions" that detectives "need answered."
Kansas City Police Capt. Steve Young made his statement as the investigation into the toddler's disappearance entered its fourth week without any suspects or leads to the girl's whereabouts.
Police are still intent on interviewing the parents, Deborah Bradley, 25, and Jeremy Irwin, 29.
"We need them to sit down apart from each other, with detectives, and answer the tough questions detectives have for them concerning what they may or may not know about anything, who came and went [the night Lisa disappeared]," Young told ABC News. "There's a whole list of things that they may know."
Young said he is "not disputing" family attorney Joe Tacopina's claims that the family has cooperated and answered other questions, such as specific questions regarding tips and leads. But that is not sufficient, he said.
"The bottom line is detectives need to sit down with them unrestricted and they need to answer questions that we need answered," he said.
The captain rejected any suggestion that the case has hit a dead end.
"It would be far from reality to call this a cold case," Young said. "We're still looking at everything."
Young made his comments as Tacopina unleashed more criticism of the investigation, telling ABC's Good Morning America Tuesday that the parents have cooperated with numerous searches and interrogations.
"It really is maddening to me to listen to this police spokesperson come out there, and instead of informing the public -- and more importantly the family -- about leads and the status of the investigation and the manhunt, he comes out and makes these statements," Tacopina said. "And, quite frankly, they've [parents] done everything they've been asked to do...They have nothing to hide. They want answers."
Young declined to comment on Tacopina's remarks other than to say, "I stand by all my previous statements."
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