Sir Nicholas Winton may have saved even more Jewish children from the Nazis than previously thought after unpublished diary reveals new 1939 rescue flight

British hero Sir Nicholas Winton could have saved even more Jewish children from the Nazi regime than previously believed, new research suggests. 

The late stockbroker is celebrated for rescuing 669 children by organising Kindertransport trains that brought them to Britain before the outbreak of the Second World War.

His story was largely unknown until he emotionally met some of those he saved on BBC show That's Life in 1988.

Sir Nicholas was portrayed by Sir Anthony Hopkins in the recent film One Life, bringing further public attention to his selfless efforts.

As well as the Kindertransport trains, Sir Nicholas was known to have helped organise three flights that brought children out of Nazi occupied Czechoslovakia on the eve of war.

But now, details of a fourth flight have been discovered in unpublished diaries of another humanitarian who worked with Sir Nicholas. 

According to the Telegraph, Doreen Warriner, Sir Nicholas's colleague in Prague, wrote in the unseen diary: 'On the 10th March, a special plane took my children from the YWCA to England, through Winton's organisation by now in charge of Trevor Chadwick.'

Ms Warriner, who as the head of the British Committee for Refugees from Czevhoslovakia was working to get children out of the country, also referenced this 'special plane'.

Her diary has been studied by historian Edward Abel Smith, who noticed a flight recorded on March 10, 1939. 

This was days before the Nazis turned Czechoslovakia into the protectorate of Bohemia and Moravia.

Another flight had a 20-seat capacity. If this was the case for the previously unknown plane, Sir Nicholas could have saved a further 20 children. 

Mr Smith told The Telegraph: 'It seems likely that there could be even more transports that Winton and his team organised that we do not know about.'

He added: 'Given that five days later the Nazis occupied the country, thousands of records were desperately destroyed, so it is somewhat unsurprising that these records might have been lost.'

Thousands of records were destroyed in the days after the Nazis fully occupied Czechoslovakia, suggesting that there could have been even more rescues.

Mr Chadwick, who became known as the 'Purbeck Schindler' for his own contribution to saving young Jews, was a schoolteacher who stayed in Prague while Sir Nicholas organised visas and foster families in Britain.

Sir Nicholas helped to arrange a total of eight trains that brought children from Nazi-occupied areas to Holland, before the youngsters came to Britain by boat.

A planned ninth train never with 250 children onboard never left Czechoslovakia due to the outbreak of war on September 1, 1939. All but two of those children died in the Holocaust.

Sir Nicholas was plagued by guilt for the rest of his life. 

Dame Esther Rantzen, the presenter of That's Life, said last year he had told her over the phone before his TV appearance that he 'hadn't saved enough'.   

'I said why do you say that. And he said because there was a last train, it had 250 children on the train... they had closed the border and all those children had to be taken off the train.

'That moment is reconstructed in this feature film. It traumatised Nicky, and I think for him, the memory was of his failure,' she added.

On That's Life in 1988, Sir Nicholas was seen sat in an audience of men and women. 

Unbeknown to him, all were survivors who had come to Britain on the Kindertransport. 

Producers of the programme had got hold of Sir Nicholas's scrapbook, which recounted his rescue of the Jewish children.

As he sat in the front row on That's Life, the audience and viewers at home were told his life story.

Near the end of the show, he was introduced to two women, Vera Gissing and Lady Grenfell-Baines.

Producers then asked Sir Nicholas to come to the following Sunday's show. He agreed, but he said he wanted to bring his wife.

During that famous broadcast, presenter Esther Rantzen asked: 'Is there anybody in our audience tonight who owes their life to Nicholas Winton? If so, can you stand up please.'

After a short pause, four rows of middle-aged people stood up. All of them owed their lives to Sir Nicholas, who was knighted for his heroics in 2003.

He stood up slowly, turned round, and couldn't quite believe how many there were.

He acknowledged them all and then sat down to wipe away tears.

Sir Nicholas passed away aged 106 in July 2015.