Remembering Sept. 11: Events Planned in Mass.

Craig Allen  Getty Images Smoke pours from the World Trade Center after being hit by two planes

Craig Allen Getty Images Smoke pours from the World Trade Center after being hit by two planes

Four passenger airliners were hijacked by 19 al-Qaeda terrorists with the intention of flying them into landmark buildings.

The ceremony will kick off with a citywide moment of silence at 8:46 a.m. - the moment hijackers flew American Airlines Flight 11 into the north tower.

A third plane, American Airlines Flight 77, was crashed into the Pentagon (the headquarters of the United States Department of Defense) in Arlington County, Virginia, leading to a partial collapse of the building's western side.

At the Flight 93 National Memorial in Shanksville, Pennsylvania, construction will soon begin on a 93-foot tower to commemorate the 40 lives lost in the hijacked plane that crashed into the countryside on September 11, 2001. The attacks killed 2,997 people, injured over 6,000 others, and caused at least $10 billion in infrastructure and property damage.

The commissioners unveiled a resolution in support of the September 11th National Memorial Trail last week.

The Department of Homeland Security was established in response to the attacks of September 11, 2001.

According to the proposed map on the organization's website, the looped trail will travel south from the World Trade Center into New Jersey and follow a large portion of the Delaware & Raritan Canal before crossing into Morrisville on the Calhoun Street Bridge.

On Sept. 11, 2001, four planes were hijacked and crashed into prominent United States landmarks, most notably the north and south towers at the World Trade Centre in NY.

GettyA fireman works in front of the debris of the World Trade Center towers.

There are also events planned for MA in remembrance of the terror attacks. The lights representing the Twin Towers of the original World Trade Center will then fade into dawn tomorrow.

The plane's target still remains unclear but theories refer to the White House, the U.S. Capitol, and the Camp David presidential retreat in Maryland, or one of several nuclear power plants along the eastern seaboard.

GettyPeople stand and watch fire consume the World Trade Center towers.

The impact resulted in a massive explosion that collapsed the twin towers in a massive cloud of dust and smoke.