By Reuters Staff 4 Min Read WASHINGTON (Reuters) - The nation’s capital on Friday continued to boost security by shutting down access to iconic landmarks and erecting vehicle checkpoints at a security perimeter surrounding central Washington ahead of President-elect Joe Biden’s Jan. 20. inauguration. Members of the National Guard secure the area near the U.S Capitol ahead of U.S. President-elect Joe Biden's inauguration, in Washington, U.S., January 15, 2021. REUTERS/Eduardo Munoz Presidential inaugurations are always tightly secure events with operations led by the U.S. Secret Service, but this year’s measures have been amped up after Trump supporters stormed the Capitol on Jan. 6 in a bid to prevent the final certification of Biden’s victory. Law enforcement officials have warned of threats and armed groups in all 50 states.