Read more about this story from CNN affiliate WMUR.
(CNN) -- Tips continued to pour in Saturday in the disappearance of an 11-year-old New Hampshire girl, but so far none have led to the child, Assistant Attorney General Jane Young said.
"We are looking at those tips. We are honing the investigation based on those tips," she said.
The FBI offered a $25,000 reward for information leading to an arrest in the disappearance of Celina Cass, who vanished between 9 p.m. Monday night and the time her parents went to wake her Tuesday morning. Officials said a private citizen is also offering a $5,000 reward for information leading to Celina Cass' return.
Dive teams will be brought in Sunday to search area ponds, Young said.
About 100 investigators -- including FBI agents, New Hampshire and Vermont state police, local authorities and employees of the state's Fish and Game Department -- have been searching for Celina door-to-door in the small, tight-knit town of West Stewartstown.
"We are still aggressively, aggressively searching and hoping to bring Celina Cass home," FBI Supervisory Special Agent Kieran Ramsay said Saturday.
Help has come from as far as Virginia -- including from FBI headquarters in Quantico -- Pennsylvania and New York, Young said
Celina was last seen in her room, at her computer, at about 9 p.m. Monday night, according to police. CNN affiliate WMUR reported that her parents told authorities the girl was gone when they went to wake her up Tuesday morning.
Authorities have offered few further details on the case and an Amber Alert has not been issued. Young said that investigators are looking at computer and phone records, trying to find clues.
Celina's disappearance has rattled many in West Stewartstown, a town along the border with Vermont and Canada with a population of about 1,000 people, according to the state of New Hampshire. Friends and relatives have spent much of the past few days putting up posters and doing what they can to find the girl.
Friends have set up a Facebook page, "Missing Celina Cass," with one of the fliers serving as a profile picture. According to the flier, Celina is 5 feet 5 inches tall and weighs 95 pounds, with long brown hair and brown eyes. She was last seen wearing a pink shirt, pink pullover and blue shorts.