In pictures: Terror strikes New York

Horrifying images of the moments two planes hit the 110-storey World Trade Center in New York.

Smoke billowed out of the World Trade Center after the first plane hit it

Less than 18 minutes later, another plane closed in on the other tower

The plane seemed to swerve to hit the other tower

The second plane caused a massive explosion and fire on the second tower

The fireball generated by the second collision spread out across both the towers

Terrified New Yorkers saw the explosion from the second plane as they hurried to flee the area

The South Tower collapsed in a cloud of debris and smoke

The collapse obscured much of downtown Manhattan

Moments later much of the landmark disappeared behind smoke (pic: Adam Rothschild)

The collapse of the second tower, the North Tower, followed shortly afterwards