At least seven accidents along Interstate 20 through Vicksburg and Warren County were reported to authorities Thursday as overnight rain turned to ice and glazed roads and bridges.

“The roads are holding this slush right now, but as temperatures drop it’s turning to ice and snow,” Sheriff Martin Pace said. “Use extreme caution on the roads if you need to be out.”

Vehicles were reported overturned on I-20 near Bovina overnight, one before dawn and a second at about 7:20 a.m. The extent of injuries wasn’t immediately clear, Warren County Emergency Management Director John Elfer said. Ice covered bridges large and small, as traffic crossed them only with the aid of sand put down by city and county road crews. Slush is expected to stay on lesser-traveled roads and bridges countywide, particularly those obscured from any daylight by trees.

Nearly an inch of rain fell overnight in the city. Vicksburg Water Treatment Plant recorded .82 inches of precipitation. The wintry weather is expected to subside by 11 a.m., though a winter storm warning remains in effect until 3 p.m., according to the National Weather Service. Highs are expected to top out at the freezing mark, with lows Thursday night around 21. Temperatures are forecast to rebound to 43 Friday, then to 56 by Saturday.

Temperatures on Wednesday dropped 48 degrees as a storm system that produced snow in the Ohio River Valley and lower Midwest moved across Warren County.

Government offices in Vicksburg and Warren County were closed, including the county courthouse and City Hall.

“We’re sorry for the inconvenience, but we do err on the side of caution,” Mayor George Flaggs Jr. said.

Classes were canceled countywide for all public and private elementary and high school students. Alcorn State University decided Thursday to close all three of its campuses, in Lorman, Vicksburg and Natchez. Hinds Community College closed all six of its locations Thursday due to icy conditions.

Entergy Mississippi reported 47 customers out of power Thursday in Warren County. Officials with the utility said crews from its Louisiana and Texas subsidiaries were at the ready to help with power outages in the state. Customers were advised to stay away from downed power lines.

Vicksburg’s casinos, which have some of the steepest access roads in town, were open for business but closed some of their entrance and exit ramps as icy rain fell. Ameristar Casino closed their south ramp and left the north ramp open for safety purposes, public relations manager Lori Burke said. Access to Riverwalk Casino was closed as of 8:30 a.m. despite being open for business. Sand covered the lone open access road from Lady Luck Casino, on the south end of the property, as the steeper entrance to the north was closed.

Staff reporter Josh Edwards contributed to this report.