The National Aquarium in Baltimore will remain closed on Thursday and Friday because of an electrical outage at its Pier 3 building, according to officials.

The power outage began Wednesday night, and animal care staff was immediately called in to ensure the animals were in good health, according to Kristin Zissel, a spokesperson for the aquarium.

A power generator is helping keep the animal facilities running in the meantime, she said.

Zissel said staff will continue to be on call around the clock as the electrical issue continues to be fixed.

Those who bought tickets to the aquarium for Thursday and Friday will be automatically refunded. Any further closures at the aquarium will be announced online.

Several people who arrived at the National Aquarium on Thursday were disappointed to see it closed.

Dan Chote, who drove from State College, Pennsylvania, was there with his two sons to visit the aquarium.

“That’s such a bummer,” he said while looking at the “closed” sign at the ticket booth. Though he said he would be back in the future.

This article may be updated.