The Secret Service-led effort to fortify the event will create a more solemn production on the steps of a Capitol building, the scene of a bloody siege by supporters of outgoing President Donald Trump, the person said.
Far fewer people than usual will attend the ceremony, which already had been scaled back due to the COVID-19 pandemic and now also will have a bulked-up security detail, he said.
The FBI has warned of armed protests being planned for Washington ahead of the event, a federal law enforcement source said.
The National Guard prepared to send up to 15,000 troops to Washington, and the Secret Service said it would begin its special security arrangements almost a week earlier than originally planned. Up to 10,000 will arrive by the weekend according to two U.S. officials.
Some of National Guard troops helping to secure the area ahead of President-elect Joe Biden's inauguration will be armed, they said.