LUMBERTON, N.C. (AP) - Volunteer firefighters drove their military-surplus truck with 4-foot tires into dark flood waters, after torrents from Hurricane Matthew sent the Lumber River overflowing its banks on North Carolina's coastal plain.

Cruising past a mortuary, grocery and homes in a flooded area of in Lumberton, they joined U.S. Marshals and water rescue teams from as far away as New York and New Jersey on Monday. They were focused on rescuing about 1,500 people who were trapped when the river unexpectedly rushed out of its banks, up their stairways and into buildings.The rescue teams were expected to be back at work across eastern North Carolina on Tuesday as the deluge rolled downstream toward the Atlantic Ocean. At least three rivers were forecast to reach record levels, some not cresting until Friday.The half-dozen men from the nearby town of Rayham spent about 10 hours Monday aboard their truck - usually used for fighting brush fires in this swampy, rural southeast corner of North Carolina. They ferried to safety the people in inflated dinghies or bass boats who met the truck on the neighborhood's main street."We've got it nowhere near this bad," said Jimmy Hunt Jr., son of the chief of the volunteer fire department in Rayham.Hurricane Matthew killed more than 500 people in Haiti and at least 23 in the U.S. - nearly half of them in North Carolina. At least three people were missing.In addition to the 14 storm-related deaths in North Carolina, there were five in Florida and three each in Georgia and South Carolina. One death was reported in Virginia.Also in Lumberton, authorities said a man was fatally shot by state trooper in confrontation amid flood waters in hard-hit Lumberton.The full extent of the disaster in North Carolina was still unclear, but it appeared that thousands of homes were damaged, and more were in danger of flooding.Robert Barnhill, 83, and his wife Katie, 81, left everything inside their Lumberton home but their medications, a couple of blankets and a pillow."The water's up to the porch now, so it's got one more step to go" before entering their home of 35 years, Robert Barnhill said after being rescued Monday afternoon. "I've never seen a flood like this before."Rescuers still had not made it to all the submerged cars or figured out exactly how many people are missing or dead, county Emergency Management Director Stephanie Chavis said."I've been here right at 28 years," Chavis said. "This seems to be the worst one we've had in my career."Elsewhere in North Carolina, officials said a dam has been in danger of a breach after the storm was holding, so far. Crews worked until about 2 a.m. Tuesday to get sandbags in place to reduce the threat at Woodlake Dam in Moore County near Vass, Deputy Public Safety Director Scott Brooks said.Brooks said crews would be out again later Tuesday morning to finish. The work would need to be inspected before residents could return home.In many areas, Matthew's aftermath was compared to Hurricane Floyd, which caused $3 billion in damage and destroyed 7,000 homes as it skirted the coast in 1999.Officials were concerned that other cities could suffer the fate of Lumberton, a community of 22,000 people about 80 miles from the ocean. With electricity cut off in the storm's wake, there was virtually no gasoline, water or food for sale.The Rev. Volley Hanson worried that stress from the lack of running water and electricity might push people over the edge. Robeson County, which includes Lumberton, had North Carolina's highest violent crime rate in 2014."The cash is going to be running out. We've already got street vendors hawking water, Cokes and cigarettes. Cigarettes are at seven bucks a pack," Hanson said. "It's nuts here, and it's going to get worse."The Lumber River crested 4 feet above its record level Sunday in Lumberton and was forecast to remain there until Saturday. A levee appeared to fail early Monday, but officials later concluded that floodwaters had flowed around it.River flooding was happening in other places, too. In the tiny town of Nichols, South Carolina, downstream from Lumberton, at least 100 people spent the night on the third floor of the town hall.Interstate 95 - a major artery for the East Coast - was closed in Lumberton and engineers had no estimate on when it would reopen. Driving was difficult, if not impossible because hundreds of roads were closed, in some cases isolating entire towns. Dozens of school districts and East Carolina University canceled classes for the entire week. Nearly 1 million people in North Carolina and South Carolina were without power, two days after the eye of the hurricane moved out to sea.Authorities in coastal Georgia and South Carolina warned residents it may take days or even weeks to restore electricity and clean up all the debris. People who tried to go home but were blocked by authorities who said the damage was still too severe grew increasingly frustrated.Matthew's flooding in North Carolina was made worse by heavy rains in September. Many areas east of I-95 got at least twice their normal amount of rain in September, in part because the remnants of Tropical Storm Julia parked off the coast for several days.---Associated Press writers Jack Jones, Meg Kinnard and Jeffrey Collins in Columbia, South Carolina; Tom Foreman Jr. in Winston-Salem, North Carolina; and Gary D. Robertson in Raleigh, North Carolina, contributed to this report.