Family pleads for return of missing Tucson girl April 25, 2012 -- Updated 2144 GMT (0544 HKT) Police are scaling back their search for Isabel Mercedes Celis, an official said Wednesday. NEW: "We will do anything for her," Isabel Celis' father says The 6-year-old has been missing since Saturday morning Police still have about 300 leads to follow in her disappearance, chief says Police say they've methodically searched much of the area around her home Tucson, Arizona (CNN) -- The parents of missing 6-year-old Isabel Mercedes Celis pleaded for her safe return Wednesday after police said they had scaled back their search for her. "Please, please -- to the person or persons who have Isa, tell us your demands," said her father, Sergio Celis. Tell us what you want. We will do anything for her. Isabel was reported missing from her family's home Saturday morning. She was last seen by family members when she went to bed at 11 p.m. Friday, and a screen was found removed from one of the home's windows, according to Tucson police. Celis and his wife,Becky,thanked volunteers who have been taking part in the search. Addressing his daughter directly, he said, "We miss you so much, and we will never give up. We will never give up looking for you. Celis said the couple would increase the current $6,000 reward offered to help produce a break in the case. He did not say how much, however, and the couple took no questions after delivering their statement. Tucson Police Chief Roberto Villaseñor said police have methodically searched a 3-mile radius around the family's home and a local landfill. Investigators were wrapping up their search of the family's home and working to "transition the house back over to the family" Wednesday afternoon, he said. Villaseñor said investigators are still pursuing more than 300 tips, but the number of officers committed to the search is being pared back. "It doesn't mean we've abandoned the search," he said. We have just scaled back some of our personnel. We have accomplished the majority of the search of the sites we wanted to visit. We are now concentrating our search on maybe some focal points where we are hoping we'll have a little bit more success. Tucson authorities have described the child's disappearance as suspicious, but have not identified any suspects in Isabel's case or indicated what they believe may have happened to her. HLN's Natisha Lance contributed to this report.