Americans have paused to reflect on a day they cannot forget. They are remembering the nearly 3,000 people killed 22 years ago in the September 11 attacks.

Families of the victims, fire fighters and others attended a memorial on Monday at Ground Zero in New York. They listened as the names of their relatives and friends were read aloud.

Monica Iken lost her husband, Michael, in the attack on the South Tower of the World Trade Center. "Most of the children now don't know anything. So, it's very sad to see that," she said. "But, as long as we're here, we'll keep their memory alive."

Al-Qaeda members carried out the attacks by hijacking four commercial planes. They flew two of them into the Twin Towers and another into the Pentagon. The fourth plane crashed into a field in Pennsylvania.

Twenty-four Japanese were among the dead. Some families joined in the ceremony in New York.

Sumiyama Kazusada lost his son, Yoichi. He is 86 years old and fears he may not be able to attend again. "I wanted to visit every year. But I couldn't because of the pandemic," he said. "I'm getting older and couldn't risk waiting any longer. I had to come."

US President Joe Biden stopped off on his way home from visits to India and Vietnam to attend a ceremony at a military base in Anchorage, Alaska. He told service members and first responders that terrorists targeted their freedoms but failed. He said Americans "must remain vigilant."