Police are searching for a 2-year-old boy attacked by an alligator and dragged away at a Disney hotel near Orlando, authorities said.

The incident happened during movie night Tuesday on the beach of the Grand Floridian Hotel.

The family was relaxing at a sandy area near the Seven Seas Lagoon on the property.

They were "wading just in the water along the lake's edge at the time that the alligator attacked the child," Orange County Sheriff Jerry Deming said.

"Based upon my 35 years of law enforcement experience, we know we have some challenges ahead at this time," he said. "We're not leaving until we recover the child."

The family of five -- parents and three children -- is vacationing from Nebraska, Deming said. He added that no nuisance alligator reports have come in the region recently.

CNN staff on the scene spotted at least 10 emergency vehicles, and the beach has been cordoned off.

Witnesses told CNN a movie was being screened on the beach that evening.

A helicopter with a search light scoured the lagoon as a handful of Disney employees ushered people away from the sidewalks overlooking the beach.

(CNN)