National Grid said more than 7,000 customers in Rhode Island could be without natural gas service for several days because of a transmission supply issue, prompting Gov. Gina Raimondo to declare a state of emergency.

The utility said gas service was suspended on Monday evening to 7,100 customers on Aquidneck Island "out of an abundance of caution," and expects to deploy about 1,000 personnel to restore service "as quickly as possible." National Grid said gas service to the island in Narragansett Bay, was cut after "experiencing a low gas pressure situation" with supplier, Algonquin Gas Transmission Co., an Enbridge Inc. subsidiary.

"We have multiple teams on the ground assessing the situation and will continue to provide updates," National Grid said. "This restoration process may be a multi-day event for those impacted. Recognizing the extreme cold temperatures, we are working with state and local leaders to address the situation…”

The area is safe, it said, and the situation is under control. “We know how important your gas service and safety is, and we apologize for any inconvenience this has caused, especially in the cold weather."

Raimondo declared a state of emergency in Newport County, which includes Aquidneck Island, and activated the Rhode Island National Guard. The outage area includes the cities of Middletown and Newport.

"This situation is still very serious," Raimondo said during a press conference Tuesday. "The good news is that at this point in time, there are no reports of any major injuries, fatalities or hospitalizations. Of course, we continue to monitor it, but all things considered we were able to get through the night.

"My primary message to people is that it is not safe to stay in your house. This is going to be a multi-day event, possibly a week or longer." The governor said National Grid would reimburse or provide vouchers for hotels.

National Grid Rhode Island President Tim Horan said the utility noticed a lack of supply coming from Algonquin at about 11 p.m. Monday, creating an underpressure issue that hit the southern end of the island the most, which includes Newport and parts of Middletown.

"The integrity of our system is safe and intact," Horan said. However, on Monday night, "the pressure here dropped so much, from Route 138 south that we made the decision, all on safety, to shut off this part of Newport.” North of Route 138, “the pressure stayed high enough for us to keep the system running safely."

Horan said about 340 customers in Middletown were affected by the disruption. At the time of Tuesday's press conference, he said gas service had been physically shut off to about 305 customers, with the remaining 35 shutoffs expected to be performed Tuesday. "Once we get in and shut off those customers today, we will then regas that section of Middletown and start relighting Middletown."

It was unclear if an explosion Monday evening on the Texas Eastern Transmission (Tetco) system in southeast Ohio was related to the incident in Rhode Island. Natural gas flows were reportedly cut by more than 1 Bcf/d on Tetco, an Enbridge subsidiary, and the impacts were felt as far away as Louisiana.

Newport Public Schools were closed Tuesday, and the district said it would "keep families updated as best as possible...regarding any future school closures." The district had opened a warming center at Gaudet Middle School in Middletown.