Representatives of Polish President Andrzej Duda, US Ambassador Georgette Mosbacher and Warsaw City Hall laid flowers at a monument commemorating the six Polish citizens who were killed in the 9/11 attacks.
Aside from the officials, the Polish State Fire Service sent a large delegation to the ceremony.
Numerous Polish-Americans without Polish citizenship also lost their lives when Islamist terrorists crashed two hijacked planes into the World Trade Center, while another plane hit the Pentagon and a fourth crashed near Shanksville, Pennsylvania after passengers had realised what awaited them and decided to fight their way into the cockpit.
The Warsaw memorial to the Polish victims of the attacks was unveiled on the first anniversary of the attack. The monument is located on the main avenue of Skaryszewski Park in central Warsaw