Sirius was a Yellow Labrador police dog for the Port Authority of New York and New Jersey Police Department responsible for explosives detection in the World Trade Center complex.

On 11 September 2001, Sirius and his handler Lieutenant David Waymond Lim were in a police office below the South Tower of the world trade center complex when upon feeling the shock of American Airlines Flight 11 crashing into the North Tower, he put Sirius in his kennel and went to investigate.

Lt. Lim was inside the North Tower when it collapsed, and was rescued 5 hours later.

The remains of Sirius were recovered on 21 January 2002 with a Police Honor Guard present.

[4] In April 2002 the British Embassy in Manhattan posthumously awarded Sirius the Victoria Cross.