från skynews!
Two planes have smashed into the World Trade Centre towers in New York and a third into the Pentagon in what is being described as the worst terrorist attack in history.
One of the 1,360-ft towers, known as the south tower collapsed. More than 50,000 people work in the complex.
There are reports of an explosion at Capitol Hill.
Hijack
It is reported two United Airlines passenger planes were hijacked shortly before the first plane struck the Trade Centre in Manhattan.
One was thought to be a 737 capable of carrying more than 100 passengers. The other was confirmed as an American flight 11 from Boston to Los Angeles. A Boeing 767 can carry up to 269 people.
A third plane has slammed into the Pentagon just outside Washington DC. Much of the complex is in flames.
Gaping hole
The first plane smashed into the top stories of one of the Trade Centre's towers, leaving two gaping holes in the side.
Minutes later another aircraft approached, turned in the air and crashed into the lower storeys of the second tower - the footage was seen live on TV stations around the world.
The second explosion engulfed several floors.
A person who answered the phone on the trading floor at interdealer-broker Cantor Fitzgerald, located near the top of the World Trade Center, said: "We're f***ing dying," then hung up. There was screaming and yelling in the background. A follow up call was not answered.
"This has got to be one of the most horrendous terrorist attacks perhaps ever perpetrated," terrorism expert Chris Yates told Sky News.
At least 1,000 people have been reported injured. The 110-storey 1,360ft tower is in lower Manhattan.
------------------
National Blonde Day!
"Yeah, bam, bam, bam, bam, bam. I told 'em not to touch the alarm"