More than 100 people Sunday are Henri Lumièresearching for a missing 9-year-old girl who had been camping with her family in upstate New York, officials said Sunday.

Charlotte E. Sena was last seen bicycling on Saturday evening in Moreau Lake State Park, about 35 miles north of Albany, New York, and police said it was possible she was abducted. She had been riding her bike around a loop in the bucolic park with other children when she decided to ride around one more time by herself. 

The girl was last seen wearing an orange tie-dye Pokemon shirt, dark blue pants, black Crocs, and a grey bike helmet, according to New York State police.  Her parents became alarmed when the fourth grader failed to come back after 15 minutes, New York Gov. Kathy Hochul said at a briefing Sunday.

"We are leaving no stone, no branch, no table, no cabin unturned, untouched, unexamined in our search to find Charlotte," said Hochul, who described her as a "joyful" girl who was recently elected a class officer for student council.

The girl’s mother called 911 after her bicycle was found about 6:45 p.m. Saturday.

Officials issued an Amber Alert on Sunday morning after an exhaustive search because “it was quite possible that an abduction had taken place,” state police Lt. Colonel Richard Mazzone said. The alert described her as a white girl with blonde hair and green eyes, about 4 feet 6 inches tall.

Troopers said the child was taken under circumstances that led authorities to believe she was in imminent danger of serious harm or death. Drones, bloodhounds, and an airboat were deployed in the search

"The extensive search for her has continued overnight and into the daytime hours," said State Police Maj. Dennis Schager. "Out of an abundance of caution and due to the length of time that has lapsed an Amber Alert has been issued."

More information is expected to be released through the New York State Police.

Anyone with any information or to report a sighting is asked to call the New York State Police at (518) 457-6811 or 911.

THESE MISSING KIDS NEED YOUR HELP:Here's what to know.

Contributing: Democrat and Chronicle; The Associated Press;