Police in San Antonio, Texas, may have narrowed down the timeline in the disappearance of 3-year-old Lina Kihl.

As previously reported, Lina had been at a playground at the San Antonio apartment complex where she lived with her family when she disappeared on December 20. Her mother briefly separated from the girl and could not find her when she returned to the playground, where police have said other children and adults were present. San Antonio police have said they are treating the disappearance as a missing person case though Texas authorities issue an AMBER Alert after the girl was reported missing on December 20, and it remains active.

The FBI is assisting the San Antonio police in the search for the 3-year-old girl, and investigators have been working to obtain physical evidence, including surveillance camera footage from the area. Citing law enforcement sources, KXAN reports that police are now focusing on an 18-minute period on the evening of December 20, between 4:49 p.m. and 5:07 p.m. The report indicates that Lina is no longer visible on any surveillance camera or seen by witnesses beginning at 4:49 p.m. The report does not confirm why the time period police are focusing on ends at 5:07 p.m., though Lina’s mother is believed to have discovered her daughter missing from the playground around 5 p.m. on that Monday. Lina’s family reportedly searched for her themselves, including at the family’s apartment, and reported her missing around 7 p.m. that evening.

According to the KXAN, police do not have any new leads but are continuing to collect tips. Authorities have not named any suspects or persons of interest in the girl’s disappearance.

Anyone with information is urged to contact the San Antonio police missing person unit at 210-207-7660.

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