The anniversary will be marked by several events across the country.
Saturday marks 20 years since the 9/11 terrorist attacks.
Hijackers crashed two commercial airliners into the World Trade Center, striking the north tower at 8:46 a.m. followed by the south tower at 9:03 a.m. At 9:37 a.m., a third hijacked airline crashed into the Pentagon.
Twenty-two minutes later, the World Trade Center’s south tower collapsed. A fourth hijacked plane crashed into a field in rural Shanksville, Pennsylvania, at 10:03 a.m. after passengers fought with and overcame the hijackers.
At 10:28 a.m. the World trade Center’s North Tower collapsed.
In total, 2,977 people were killed, including many New York City first responders.
The anniversary will be marked by several events across the country, including the annual commemoration at the World Trade Center Memorial in downtown Manhattan.
Here are the latest updates from the day. All times are Eastern.