Missing 11-year-old Madalina Cojocari's parents "clearly" know more than they've told investigators, local police said on Tuesday.
The Cornelius Police Department offered an update into the steps it's taken -- with the help of the FBI and the North Carolina State Bureau of Investigation -- in the 12 days since Cojocari was reported missing.
"We know everyone has a lot of questions," Capt. Jennifer Thompson said in a video posted to Facebook. "We also have questions and are doing everything we can, with proper legal authority, to get those answers."
She added, "This is a serious case of a child whose parents are clearly not telling us everything they know."
The FBI last week released a surveillance video that investigators said showed the 11-year-old leaving her school bus on Nov. 21, which they said was the last confirmed sighting of the child.
Her parents told investigators she's been missing since Nov. 23, but she was reported missing on Dec. 15, according to a police report.
Her parents -- mother Diana Cojocari, 37, and stepfather, Christopher Palmiter, 60 -- were both arrested on Dec. 17 and charged under a North Carolina law that requires guardians to notify police within "a reasonable time" when a child goes missing.
Each faces a felony charge of failure to report the disappearance of a child to law enforcement, police said in two statements. Both are scheduled to appear on Wednesday morning in Mecklenburg County Court, according to the local sheriff's website.
Investigators have developed and followed about 250 leads in the 12 days they've been searching for the girl, Thompson said on Tuesday. Those leads have been "across state lines and across the globe," she said.
"We have interviewed hundreds of people in North Carolina, other states, and, again, across the globe," she said.
Police have knocked at about 245 home as they've gone door-to-door in the Victoria Bay neighborhood around Madalina Cojocari's home, Thompsons said. Investigators have "scoured" hours of surveillance video from local businesses.
"Investigators received multiple search warrants for Madalina's home, to make sure we legally gathered each and every piece of evidence to find Madalina," Thompson said.
Police said the girl's school reached out to Diana Cojocari "several" times between Nov. 23 and Dec. 15, when the mother reported the girl missing at her school.
"One of the challenges in the case, simply put -- we were not notified she was gone, a delay of three weeks," Thompson said.
Officials have worked to piece together a timeline of Madalina Cojocari's disappearance, according to an arrest sheet obtained by ABC News affiliate WSOC.
Diana Cojocari told police she'd last seen the girl at about 10 p.m. on Nov. 23, according to the arrest sheet, which was dated Dec. 17.
Diana Cojocari told police "Madalina went to her room that night to go to bed. Diana stated her and her husband, Christopher Palmiter, argued that night and the next morning he drove to his family's house in Michigan to recover some items," law enforcement officials wrote in the arrest sheet.
Second vigil held for Madalina
Diana Cojocari said she went to check on her daughter at about 11:30 a.m. on Nov. 24, but the girl wasn't in her room, according to the arrest sheet. Police said Diana Cojocari told them that she'd waited until Palmiter returned home, at about 7 p.m. on Nov. 26, to ask if he knew where Madalina Cojocari was.
Police "asked Diana why she did not report Madalina missing until" mid-December, and she "stated she was worried it might start a 'conflict' between her and Christopher," officials wrote in the arrest sheet.
Palmiter told police that he'd asked Diana Cojocari where Madalina was when he'd returned from his trip, officials wrote.
"Chris stated he spoke with Diana several time(s) about Madalina's whereabout(s) over the next three weeks," the arrest sheet said, "and both stated they did not know where she was but they did not contact the police to report Madalina missing."
ABC News' Victoria Arancio contributed to this report.