9/11 anniversary: America remembers lives lost on one of its darkest days

Fourteen years ago today, terrorists hijacked passenger planes and rammed two into New York City's World Trade Center, and a third one into the Pentagon in Washington.

A fourth jetliner crash-landed on an empty field in Pennsylvania.

By the time the carnage was over, terrorists had killed 2,977 people in one of the deadliest attacks on American soil.

People, buildings and planes fell from the sky. Terrified strangers became friends as Americans united on a day that changed the world forever.

Today, like every other anniversary after it happened , a resilient nation will look forward to the future, but remember the past.

The Federal Bureau of Investigation in Washington, says it has picked up no specific or credible threats linked to the anniversary of the September 11 2001 attacks on the United States. 

FBI director James Comey said it is closely watching for threats from al-Qaeda and ISIS.

CNN/News24