PICTURES: Possible Tornado Touchdown In Elmira

COMPLETE COVERAGE: Damage Photos  | On Scene Interview  | Eliot's Amazing Lightning Strike Map  | Campgrounds Evacuated

(AP) Power lines and trees were toppled and hospitals were placed on disaster alert but there were no reports of injuries after a possible tornado hit the city of Elmira Thursday afternoon, Chemung County Office of Fire and Emergency Management spokeswoman Karen Miner said.

A state of emergency and curfew were in effect until 8 a.m. in the city, with only emergency vehicles allowed on the streets while fallen trees and power lines were being cleared, Miner said. A shelter was set up at the Elmira Free Academy for residents who didn't want to stay in homes without power, she said.

Gov. Andrew Cuomo declared an emergency for surrounding Chemung County to allow the state to mobilize state resources to assist local governments. "This state of emergency declaration will help the state get critical resources to communities that were hit the hardest," Cuomo said.

There were reports of isolated fires, and roofs torn off small structures, and people trapped in vehicles because of downed power lines."

About 16,000 utility customers in Chemung County were still without power early Friday. About 17,000 other utility customers in the state also were without power..

"New York State Electric & Gas is working through the night ... to restore power and hopefully a lot of it will be on by tomorrow," Miner said. She said the main roads had been cleared, but that numerous side roads were "still impassable."

National Weather Service meteorologist Dave Nicosia said a helicopter was being dispatched to the area to assess the damage and determine if it was a tornado.

Cuomo said utilities were sending crews from western New York and Rochester to the Elmira area near the Pennsylvania border to assist with repairs and power restoration.

The National Weather Service issued multiple severe thunderstorm warnings across the southern half of New York throughout the day as storms moved eastward across the state. High winds, hail, and heavy rains brought down trees in numerous communities in western and southern New York.

Authorities evacuated campers in tents from 10 state campgrounds across the state as a precaution Thursday afternoon in advance of the storms.