A search crew of nearly 20 people descended on a Texas landfill on Monday as authorities hunted for a missing toddler last seen more than two weeks ago.

Nadia Lee, 2, was last seen at her father’s Pasadena apartment on Oct. 16. Two days later, her father, Jyron Charles Lee, was arrested and charged with the murder of Nadia’s mother, Nancy Reed. Authorities believe Lee, 26, strangled Reed, 22, at a hotel in Clear Lake during an argument over how to discipline their kids, according to the Houston Chronicle.

Lee remained in the Harris County Jail under a $250,000 bond on Monday. Police have said it’s possible he could face more charges related to Nadia’s disappearance.

Family members told ABC13 that Lee and Reed had had five children together. The outlet reported that two other toddlers, aged 1 and 3 years old, were present at the time of Reed’s murder. The pair were unharmed and remanded to Child Protective Services.

“It is heartbreaking. It really is,” Nadia’s grandmother Nora Reed told ABC13. “My heart is breaking in half. I just hope we find the baby, we find Nadia.”

Texas EquuSearch, a Houston-based search and recovery group, confirmed it had expanded its investigation to the Coastal Plains Recycling and Disposal Facility, with crew members roping off a site roughly the size of a football field. It was not immediately clear what evidence led the group to the landfill, which is located on private property in the city of Alvin.

“Eighteen people that are literally just cutting open every bag,” Tim Miller, Texas EquuSearch’s founder, told Houston station KHOU. “I’m hoping that anything’s not going to end up in a landfill. But for right now, wherever the ending comes up, you know, it needs to have an ending.”

Officials said that it’s possible the crew, using heavy machinery, including two track hoes and one bulldozer, will need to dig as deep as eight feet.

At the beginning of the search for Nadia, a Houston Police Department sergeant said investigators were conducting a homicide investigation, according to ABC13. Investigators believe that the 2-year-old was killed in Charles’ apartment and then moved, sources told the outlet.

Surveillance footage has shown Lee walking around a dumpster near his apartment complex with a stroller, investigators said.

“I don’t think this is going to have a positive outcome we would like to have,” said Miller. “One of my biggest fears is there may not be an outcome.”