Argentina's former President, Nestor Kirchner, has died after suffering a sudden heart attack, doctors say.
Mr Kirchner had been operated on in September for heart problems. His wife, Cristina Fernandez de Kirchner, is the current president of the country.
Here Argentineans react to the news of Mr Kirchner's death.
I believe it is a sad loss of course for his family, but under Mr Kirchner Argentina back-pedalled in time to the 1970s, tainting all his administration's (and his wife's) with ideology instead of helping move Argentina forward into the 21st century. Maybe now Argentina can move on with a lot of pending issues which have been caused by seven years of this couple. Eduardo Bennett, Buenos Aires
We are very saddened by the news. It is a terrible loss for our country to lose such a person and politician. We send our condolences and support to his family. Lorena, Argentina
I am shocked and saddened by the death of former Argentine President Nestor Kirchner. Although I disagreed with his politics, attempts to subvert the constitution and authoritarian tendencies, I still respected his contributions to Argentina. I send my sympathies to his wife, current President Cristina Kirchner and all Peronistas. RIP Nestor. Eamonn J Donovan, Buenos Aires
A real tragedy. One of the greatest politicians we've had in this country. A man of strong convictions who was brave enough to be the president of Argentina during one of the saddest and deepest economic crises, and did it so well. Luciano, Buenos Aires, Argentina
He was still playing a leading role in Argentine and regional politics. He was the president of UNASUR (the union of South American nations). It dramatically changed the political map at a crucial moment. There are presidential elections in 2011 in Argentina. The consequences are unpredictable, but a change of direction is likely. Tiago, Mar del Plata, Argentina
It was quite a shock for all of us. Although our family doesn't agree with most of the political ideas of "Kirchnerism", I must confess that the news left me speechless. There are some disrespectful people who will make jokes about it, but that's understandable because Kirchner won a lot of political opponents during his time as president. I am neither a supporter nor opponent, but it is sad to see the death of a politician with strong character, who has affected the lives of many people, negatively and positively. Matias, Rojas, Argentina
A country wakes up early in the morning, everything ready for the census that takes place today (every 10 years), and the people receive this shocking news. Despite being very critical of Kirchners's ideology and government, I can't say it's a happy day for my country. Argentina is, again, submersed in uncertainty, one year before the elections where Nestor Kirchner would have played an important part. Matias Pedulla, Buenos Aires, Argentina
Very sad to wake up to the news of our former President's death. Compared to any of the previous democratically elected presidents, Mr Kirchner's administration was characterised by concrete policies, which, in my view, were positive. Very often, some of these policies irritated some countries because they did not seem to follow their dictates and formulas. He even had the courage to stand up to the IMF, who he believed had been partly responsible for some of the hardship Argentina had suffered in 2001. He also irritated some of the media. Some also disliked his emotional style. In other words, I think that Mr Kirchner reversed the old Argentine trait of unconditionally trying to please the US. He will be sorely missed. Andres Salomon, Buenos Aires, Argentina
The death of Nestor Kirchner is an absolute shock for all Argentine society. Today is a national holiday because, after ten years, the national census is taking place. However, all the journalists are now covering this death, undoubtedly an historic one, not only because he is an ex-president, but also because he was considered to be one of the politicians with the best chances to become president next year. Besides political ideologies, a total consternation has invaded the whole country, and a scenario of uncertainty now starts. Dario, Buenos Aires
Due to Mr Kirchner's death a struggle will begin inside de Peronist Party for a presidential candidate to be chosen for next year's election. And that fight shall produce strong waves, perhaps harm, in Argentine society. Gimenez Rodolfo Pedro, San Nicolas de los Arroyos, Argentina
The death of Nestor Kirchner, the real power behind the throne, leaves Cristina Kirchner severely weakened. The question is whether she will be able to lead the country for another year until the general elections of 2011. At the same time she will need to instill a sense of peace after the increasingly bitter confrontations that have emerged in recent years with different sectors of Argentine society, such as farmers, the press, opposition parties, teachers, the church and pensioners. Lawrence Wheeler, Buenos Aires, Argentina