We are concerned about the potentially negative psychological effects of graphic details of death and destruction

William Schmidt

More than 3,000 people died in the attacks on New York and Washington, and some of the victims lived in Bergen County, which is across the Hudson River from Manhattan.

CBS has not yet formally responded to the request, but Gil Schwartz, CBS spokesman in New York, said he had not yet received the letter and would reply when he did.

'Misinformation'

Mr Schwarz defended the two-hour documentary as "responsible and sensitive" and said that the film contained no images of people being killed.

He said suggestions that the documentary contained such scenes were "misinformation".

The programme will contain footage of the approach of two planes to the World Trade Center's twin towers, taken by the French brothers Gedeon and Jules Naudet.

The event posed ethical dilemmes for TV networks

The two filmmakers were recording firefighters' training exercises about 14 blocks from the Trade Center when the attacks began.

They kept their cameras running and also recorded scenes inside the buildings of workers escaping.

Mr Schmidt said: "While we do not object to the showing of the documentary, we are particularly concerned about the potentially negative psychological effects that graphic details of death and destruction may have on the thousands of individuals who have been traumatised by the events of September 11th."

Coverage

He also asked CBS not to show the programme on 10 March, which is almost exactly the six-month anniversary of the attacks, and to screen it later in the year.

The coverage of the attacks on 11 September was watched by some 79.5 million people in the US that night, according to Nielsen Media Research.

The event posed difficult ethical problems for the networks.

They all had access to video images of victims jumping from the buildings.

NBC and Fox News showed it once then dropped it, while CBS showed the footage, and defended its decision, saying it was appropriate to the story.