A yellow Labrador Retriever, badge number 17, ninety pounds and easy-going. He graduated from the Port Newark K9 Center in July 2000 and worked the World Trade Center from that month, checking vehicles at the loading docks for explosive and sweeping areas before visitors came. He lived with his handler's family.

On the morning of the eleventh he was in the police office in the basement of the south tower with Lieutenant David Lim when the north tower was struck. Lim put him in his kennel, told him he would be back for him, and went up. Lim was buried in the collapse and pulled out five hours later; his first thought on getting free was to find Sirius, and he was put in an ambulance instead.

Sirius was found in January in the wreckage of the south tower. The men who carried him out draped him in a flag and gave him a full honour guard. He is the only animal killed in the attacks.

K9 Sirius died in the terrorist attacks of September 11, 2001. K9 Sirius was in K9 headquarters with his handler when the first plane struck the World Trade Center. His handler put him in his cage to investigate, and was unable to return before the building collapsed.

On the morning of September 11, 2001, seventy-two officers from a total of eight local, state, and federal agencies were killed when terrorist hijackers working for the al Qaeda terrorist network, headed by Osama bin Laden, crashed two of four hijacked planes into the World Trade Center towers in New York City. After the impact of the first plane, putting the safety of others before their own, law enforcement officers along with fire and EMS personnel, rushed to the burning Twin Towers of the World Trade Center to aid the victims and lead them to safety. Due to their quick actions, it is estimated that over 25,000 people were saved.

As the evacuation continued, the first tower unexpectedly collapsed due as a result of the intense fire caused by the impact. The second tower collapsed a short time later. 71 law enforcement officers, 343 members of the New York City Fire Department, 1 police K9 and over 2,800 civilians were killed at the World Trade Center site.

A third hijacked plane crashed into a field in rural Pennsylvania when the passengers attempted to re-take control of the plane. One law enforcement officer, who was a passenger on the plane, was killed in that crash.

The fourth hijacked plane was crashed into the Pentagon in Arlington, Virginia, killing almost 200 military and civilian personnel. No law enforcement officers were killed at the Pentagon.

The terrorist attacks resulted in the declaration of war against the Taliban regime, the illegal rulers of Afghanistan, and the al Qaeda terrorist network which also was based in Afghanistan.

On September 9, 2005, all of the public safety officers killed on September 11, 2001, were posthumously awarded the 9/11 Heroes Medal of Valor by President George W. Bush.

The contamination in the air at the World Trade Center site caused many rescue personnel to become extremely ill, and eventually led to the death of several rescue workers.

On May 1, 2011 members of the United States military conducted a raid on a compound in Abbottabad, Pakistan where Osama bin Laden was hiding. During the raid, they shot and killed bin Laden.