A potential key witness in the search for a missing Arizona 6-year-old has come forward as authorities expand their investigation into Mexico.
The security tapes, recorded outside a nightclub, show three women and two men walking toward the Celis family home at approximately 1:30 a.m. on April 21. Isabel was last seen around 11 p.m. on April 20.
Police are not saying what the witness has told them.
On Saturday, U.S. marshals asked Mexican authorities to expand the search for Isabel across American borders to include hotels, bus stations and businesses in the town of Sonora, CBS reported.
Authorities also conducted a visual search last week around bodies of water in the Tucson area.
Sergio and Rebecca Celis, Isabel's parents, have vowed to "never give up" the search for their daughter. Prior to obtaining the surveillance footage, police said they would scale back the search as leads in the case began to dry up.
"Obviously, I'm disappointed that we haven't found her at this point," Tucson Police Chief Roberto Villasenor said last week. "But that doesn't mean we're giving up hope or that we're not going to continue to use all the resources that we need to try and find her and follow up on these leads."
Isabel was reported missing by her father when he found the girl absent from her bedroom at approximately 8:00 a.m. on April 21.
Isabel is just under 4 feet tall, weighs approximately 44 pounds and has brown hair and hazel eyes. Anyone with any information about her disappearance or whereabouts is urged to call 520-88-CRIME.