An apparent terrorist attack has brought North American trading to a halt today.

Hijacked planes flown into the World Trade Center in New York have taken down both the twin Towers.

Simultaneous attacks at the Pentagon, a car bomb reported at the U.S. State Department and a downed airliner outside Pittsburgh are all believed to be related.

Trading in the U.S. has been halted indefinitely. It has been speculated that U.S. trading may not revive until next Monday.

The TSE opened and traded down 296 points, or 4%, to 7049, before trading was halted pending an announcement. Insurance stocks were down 6.8%, there were heavy losses in most sectors, although gold and energy are up.

The Investment Dealers Association Capital Markets Committee and Primary Dealer Money Market Committee announced the closing of the domestic bond and money markets effective 12:00 ET.

London’s FTSE closed down 274 points to 4,759, about 5.5%. The CAC 40 dropped 324 points to 4,060, a 7.4% drop. The DAX closed down 465 points or 10% to 4,205.

The U.S. dollar traded down in the wake of the news, gold and oil were both up sharply.

The largest tenant in the World Trade Center is Morgan Stanley Dean Witter & Co., occupying 12.5% of tower 2.

The total size of buildings was 1,114,800 square meters, each tower had 43,600 windows. The buildings’ capacity is 50,000 people, at least 20,000 in the twin Towers, and it attracts 90,000 visitors daily. It opened in 1970, costing US$1 billion to build, it represented 10% of downtown office space.

Also in the building according to its register were CSFB, Bank of America, Deutsche Bank, Oppenheimer Management, Salomon Smith Barney, Raymond James, Charles Schwab & Co., Keefe Bruyette & Woods, Commerzbank, Cantor Fitzgerald, Fiduciary Trust, Republic National Bank, and American Express Bank.

Numerous Asian banks also are registered as tenants including Asahi Bank, Dai-Ichi, and Hokkaido, Hyundai Securities, Brenner Securities, Tokyo Securities, National Securities.

The buildings also also housed the New York Society of Security Analysts and the New York Board of Trade. Apart from those in the buildings, other major firms are all in the immediate vicinity.

All flights in the U.S. have been grounded and the U.S. Air Force has reportedly scrambled to defend against further attacks. U.S. forces have been put on highest alert. All federal buildings have been evacuated, as have some buildings in London, England.