(CNN) -- A number of museums in Washington, DC are closing their doors again amid a spike in coronavirus cases.
The Smithsonian Institution announced on Thursday it will temporarily close all its museums and the National Zoo beginning on November 23 due to the rising number of Covid-19 cases across DC and nationwide.
"The Institution's top priority is to protect the health and safety of its visitors and staff. We will use this time to reassess, monitor and explore additional risk-mitigation measures," the Smithsonian said in its news release. "We are closely monitoring guidance from local governments, public health officials and the Centers for Disease Control and Prevention."
The museums and zoo previously closed in March, and had a limited reopening to the public in September.
"Due to the changing nature of the situation, we are not announcing a reopening date at this time," the Smithsonian said Thursday.
The US Holocaust Museum in Washington, DC, also announced that it would close on November 23, citing Covid-19.
"The spread of the coronavirus is projected to continue to increase in the coming weeks, both locally and nationally," the museum said in its statement.
Visitors with passes for times after the 22 will be immediately notified, the museum said, noting that it has not yet determined a reopening date.
The museum said it "will continue to monitor the situation and update our status, as needed on our website."
As of Thursday, there are more than 11 million reported Covid-19 cases throughout the United States and over 251,000 deaths, according to Johns Hopkins University data.
CNN's Nicky Robertson and Aileen Graef contributed to this report.