Two truckers were killed Wednesday when they drove into a chasm cut into Interstate 88 by drenching rains that flooded homes, closed roads, cut power and forced the evacuation of thousands of people across upstate New York.

The deluge that swamped the nation's capital earlier this week and is blamed for six other deaths cut across upstate New York Tuesday and Wednesday. Flood warnings were posted from the Catskills to the Adirondacks and a 50-mile section of the Thruway in the Mohawk Valley was closed due to the flooding. Gov. George Pataki planned to issue a disaster declaration.

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The two I-88 truckers — one headed east, the other west — separately drove their trucks into the 25-foot deep hole at about 6:20 a.m., said state police Lt. Robert Galletto Jr. It was raining hard at the time of the accidents and it was not clear if the truckers even saw the break, which created a jagged tear across the highway.

"All four lanes were washed out," Galletto said.

The highway was closed between exits 8 and 13 because of the gap created by Carrs Creek in Sidney. The truckers' names were not immediately released.

The heaviest hit area in New York was around Binghamton. A house was reported floating down the rain-swollen Susquehanna River near the city on Wednesday morning and whole villages to the north in rural Delaware County were cut off by flood waters. Rescue workers were searching for a vehicle washed away in Kortwright Creek; it was unclear if there was anyone in the missing vehicle.

"We have significant flooding throughout the county," said Delaware County planning director Nicole Franzese. "... Widespread power outages, bridges washed out, roads washed out, the National Guard was operating all night."

Tuesday's rainfall was the most ever received in a 24-hour period at the Binghamton airport, said National Weather Service meteorologist Theodore Champney. A total of 4.05 inches fell during the day, breaking the former one-day record of 3.57 inches set on June 11, 2001, Champney said.

About 300 people were being cared for at a Red Cross emergency shelter set up at Binghamton University after the Susquehanna, Chenango and other rivers flooded. College officials said they expected more evacuees to arrive throughout the day.

"Homes have been lost," Pataki said on CNN. "We have had to evacuate thousands of people."

More homes were evacuated a few hours to the north, near the Mohawk River. A small bridge in Charlotteville in Schoharie County was closed and floodwaters had risen to the bottom of at least one other area bridge.

Broome County emergency services director Michael Aswad reported a series of gas explosions in vacated homes in the town of Conklin, just south of Binghamton. There were no immediate reports of injuries.

Ten counties declared states of emergency amid the heavy rains: Broome, Cortland, Tioga, Chenango, Madison, Delaware, Montgomery, Schoharie, Otsego and Herkimer.

Dennis Michalski, spokesman for the State Emergency Management Office, said Pataki activated the National Guard for evacuation support and engineering. Pataki canceled a visit to New Hampshire Wednesday and was headed to Binghamton to deal with the emergency. The governor planned to issue a disaster declaration, the first step to gaining federal assistance to deal with the flooding, said William Howard, the governor's first deputy chief of staff.

Dam experts were dispatched to the Binghamton area by the Department of Environmental Conservation for inspections. Binghamton Mayor Matthew Ryan said minor leaks have been reported in the floodwall that protects downtown from Susquehanna River.

In rural Schoharie County, about 90 miles northeast of Binghamton, a mudslide closed a road and prevented emergency crews from reaching residents of a home cut off by the debris. The county's emergency management office said there were no reports of injuries from the mudslide, but reported "quite a few roads" in the farming region were closed due to flooding.

An eight-mile stretch the Thruway's westbound lane, along the Mohawk River west of Albany, was closed Wednesday, as was the National Baseball Hall of Fame and Museum in Cooperstown.

Michalski said emergency officials were tracking the storm as it moved east toward the Hudson Valley.

In the Catskills, the Esopus and Rondout creeks flooded, and the Delaware and Neversink rivers in Sullivan County neared flood stage in several spots. Homes near those rivers were also evacuated. The National Weather Service reported that the Delaware River at Port Jervis was at 18.4 feet, over flood stage of 18 feet. The river was expected to rise to near 24.3 feet by Thursday morning.

The Thruway closure between Exit 28 at Fonda-Fultonville and Exit 31 at Utica is expected to last through Thursday morning.