Lina Sardar Khil was last seen in the playground of a northwest San Antonio apartment complex during the late afternoon of Dec. 20.
The 12-member FBI Underwater Search and Evidence Response Team flew in from Washington, D.C., Monday night and searched bodies of water near the girl's family's apartment all day Tuesday, Police Chief William McManus said.
Appearing downcast, McManus said the team was merely checking a lead, of which there have been few.
"I wish I could be more uplifting. I know this looks like we're really onto something. But all we're doing here is following up," he said at a briefing at the search site.
Lina was last seen wearing a red dress, black jacket and black shoes and had her brown hair in a ponytail, police said.
The child's family had reported that she was at the playground with her mother, who had walked away briefly and found the child missing upon her return.
The family moved to the U.S. in 2019 from Afghanistan after fleeing from "threats that were posed to us," Lina's father, Riaz Sardar Khil, told KENS-TV.
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