Isabella "Bella" Grogan-Cannella, 8, was reported missing on Tuesday, Sept. 2, from her home on the 2400 block of Lakeside Dr. in Bullhead City, AZ.
The family noticed that Bella was gone around 1:30 a.m. The family told the Bullhead City police that she was not in her bed or anywhere else in the home, reports CBS Las Vegas.
The police have searched the neighborhood along with volunteers but she has not been located. The police do not know if it was a break-in or if she was abducted or walked away from the home on her own.
Chief Brian Williamson stated that many county law enforcement agencies have joined together and are searching the Colorado River by land and by boat. The FBI has also joined the investigation.
"A criminal investigation is underway," said Williamson, reports the Las Vegas Review-Journal.
Williamson said they may be asking for help from the public, but they didn't need any at this time, and would let the public know in the future if they needed volunteers.
Williamson promised to let the community know of any updates frequently so "you know what is going on," and asked that people living in the community to check their homes and property and keep an eye out for Bella.
Williamson encouraged everyone who may have information to please call the Bullhead Police Dept. at 928-763-1999.
"Let us decide if it is important information or not. Don't think that you are bothering us. Any information may just be the thing we are looking for," said Williamson during a press conference.
Bella is 4'8" tall, around 85 pounds with long dark blonde hair and blue eyes. She was wearing a green ruffled sparkly tank top and dark colored shorts. She may be barefoot.
In April 2012, Isabel Celis, 6, from Tucson AZ went missing and was last seen in her bedroom. Although the police went back to the area in Jan. 2014, no further information was found to solve the mystery of her disappearance, and she remains missing.