Tulsa police said siblings Miracle Crook, 3, and Tony Crook, 2, are still missing from their apartment near East 21st St. and Interstate 44 as of Sunday night.
Tulsa Police Chief Wendell Franklin said Sunday the department has exhausted all of its resources, likening it to finding a needle in a haystack.
“We are at our wits end trying to find these children. The possibility exists that these children are harmed,” Franklin said.
The siblings were last seen Friday morning around 8 a.m. at Ryan's Mingo convenience store near East 21st St. and South Mingo Road.
"There's only two things that can happen here,” Franklin said. “These children are either on someone's couch asleep, and the people that they're with don't know that these children are missing, or these children are dead.”
Tulsa police led a massive search in and around the lake located in middle of Shoreline Apartments over the past 24 hours. The department used dive crews, helicopters and search dogs to survey the surrounding area.
Franklin said this is one of the most complex searches they have done.
“The children cannot survive alone,” Franklin said. “There’s absolutely no way they could’ve survived 24 hours out here by themselves, so we need the public to help. I understand it’s a holiday weekend. I understand that people are at the lake and enjoying family, but we need to get this case solved.”
The children's biological mother, Donisha Willis, does not have custody of the children. Willis is now in jail accused of child endangerment and assaulting an officer.
Neighbors said Willis and the kids were acting strange last week.
"She was walking down that way in the street with her shirt on. She was sweating really hard and I was just kind of worried that I didn't see her kids,” neighbor Shamon Armstrong said. “Normally, I would see her with the kids every day.”
"I saw her about 8:30 Friday night and she seemed angry and not herself,” another neighbor said.
Police are asking anyone with information to call the non-emergency number at 918-596-9222.
TPD also said the state denied the request to issue an Amber Alert because Willis, who is the suspect, is already in custody and the department has no other information.
Related: Tulsa Police Searching For Pair Of Missing Toddlers