If people haven't received a form we will get one to them as soon as possible

Office for National Statistics

The information gathered from Sunday's snapshot of the nation will be used to help the government decide how to spend public money.

The once-in-a-decade survey is at its most complex this year, with new elements that include a question about religious denomination.

A spokeswoman for the Office for National Statistics told BBC News Online that the number of people who had not received a form had been wildly exaggerated by the media.

"It's probably a number of thousands, but thousands of people isn't a great number when we have a population of 52.5 million," she said.

"As far as we're concerned it is going very well. If people haven't received a form we will get one to them as soon as possible. But the majority of people have received the form and we have had a considerable number back."

Inner city access

The census helpline is to stay open until June to help people with queries about the survey, but forms should be returned as soon as possible.

Census statistics

23 million households surveyed 30 million census forms printed 40-41 census questions 70,000 temporary census workers Census will cost �255m

Census officials will start to chase up unreturned forms from around 9 May.

A spokesman said 5.2 million forms had already been returned, almost a quarter of those expected.

He added some delays were expected in delivering and returning the forms in areas where movement was restricted by foot-and-mouth.

He said there had also been delivery delays in inner city areas where security meant access to some households was a problem.

Newborn babies

There is an extra incentive for new parents to fill in the form as the organisers are giving out free sleepsuits to households where a baby is born on Sunday.

This is to encourage the newborns' inclusion on the form, as many are believed to have missed out in the last census.

John Pullinger, of the Office of National Statistics, said that handling 28 million forms represented a huge operation.

He told the BBC that the initial findings of the census would be ready by the summer of 2002 with detailed reports published in 2003.

"This will give all the richness of information that we need to plan services for where we put schools, hospitals and other services over the next ten years," he said.

A total of 342 people were prosecuted in the last census in 1991 for not completing their forms.

The census will help decide schools' spending

But the civil rights group, Liberty, thinks people should not be penalised for not filling in their forms.

Spokeswoman Deborah Clarke said some may not want to answer the question on ethnic origin if they feel under threat from racists.

"We wouldn't want to discourage people from filling it in as I do think there is a greater social purpose here," she said.

However she added that if someone was fined for failing to fill the form in, they were welcome to contact Liberty stating their reasons and it would consider if these were strong enough to support a human rights case.

For the first time the form can be posted back.

Up to 70,000 people have helped organise the census, which will cost an estimated �255m.

There are 40 questions in the form in England but 41 in Wales to include a survey of Welsh language speakers.

The telephone helpline, which has been set up in 12 different languages for queries about census questions, is 0845 301 2001.

Anyone who has not received a form is asked to call 0845 301 3000.