Assistant Secretary of Defense for Public Affairs John Kirby tweeted that the Pentagon is "pausing" the plan to move forward with vaccinations for detainees at Guantanamo Bay.

"We’re pausing the plan to move forward, as we review force protection protocols," Kirby said. "We remain committed to our obligations to keep our troops safe."

No detainees have been vaccinated yet, he said.

ABC News’ Molly Nagle contributed to this report.

Hard-hit California has surpassed 40,000 deaths from COVID-19, according to the state’s Department of Public Health.

At least 40,216 people in the Golden State have lost their lives, which equals about 1 in every 1,000 Californians.

ABC News’ Matt Fuhrman contributed to this report.

Nashville's Music City Center opened Saturday as a mass vaccination site.

Those 75 and older who already have an appointment booked can get vaccinated at the concert venue, according to ABC Nashville affiliate WKRN.

"We think that we’ll be able to do up to 1,000 first doses here and up to 1,000 second doses here a day, once we receive enough vaccine for that,” Metro Nashville Health Department Interim Medical Director Gill Wright told WKRN.

One case of the South African B.1.351 variant has been confirmed in the Baltimore metro region, Maryland Gov. Larry Hogan said.

"The individual has not traveled internationally, making community transmission likely," Hogan’s office said. "Comprehensive contact tracing efforts are underway to ensure that potential contacts are quickly identified, quarantined, and tested.

"The B.1.351 variant has not been shown to cause more severe illness or increased risk of death when compared to other variants. The variant is believed to be more transmissible than other strains," Hogan’s office said. "Additional research is still required to determine the effectiveness of available vaccines against the B.1.351 variant. However, initial evidence suggests that vaccines are still likely to be protective against the variant."

The United States’ first cases of the South African variant were confirmed this week in two people in South Carolina.

The official commemoration of the 76th anniversary of Auschwitz's liberation will be held online Wednesday due to the coronavirus pandemic.

The Auschwitz-Birkenau State Museum and Memorial, which is located on the site of the Nazi concentration camp in Oswiecim, Poland, is closed for visitors until at least Jan. 31 under COVID-19 restrictions set by the Polish government.

"Due to the coronavirus pandemic, the commemoration will exceptionally not be held at the Memorial, but in the virtual space," Auschwitz Memorial spokesperson Pawel Sawicki said in a statement Tuesday evening. "The main theme of the 76th anniversary of the liberation will be the fate of children in Auschwitz."

The online events will include testimony from survivors as well as a guided virtual tour of the Auschwitz Memorial, "aimed at enhancing the educational value for visitors from around the globe," according to Sawicki.

Auschwitz, also known as Auschwitz-Birkenau, was a complex of over 40 concentration and death camps run by Nazi Germany in occupied Poland amid the Holocaust during World War II. It was the largest of the Nazi concentration camps and extermination centers. More than 1.1 million men, women and children lost their lives there, mainly Jews, according to information on the Auschwitz-Birkenau State Museum's website.

In January 1945, as Soviet Russia advanced deeper into Nazi-occupied Poland toward the end of the war, Nazi officers organized a forced evacuation of the Auschwitz prisoners. Almost 9,000 prisoners, most of whom were sick or suffering from exhaustion, were deemed unfit to join the death march to Germany. The Nazis intended to kill them all as part of attempts to destroy the evidence of their crimes at Auschwitz, but only managed to murder about 700 Jewish prisoners between the departure of the final evacuation column and the arrival of Soviet forces.

Soviet troops entered Auschwitz on Jan. 27, 1945, a day now commemorated as International Holocaust Remembrance Day, and liberated more than 7,000 survivors, according to the museum's website.