Alejandro Burzaco, the former chief executive of sports-marketing company Torneos y Competencias, told the court that he had paid Delhon and an unnamed Argentinian official bribes of $500,000 annually between 2011 and 2014.

The money was for the marketing rights to domestic games in the country as Delhon served as a former lawyer for Argentina’s Football for All, a Government initiative which has broadcast rights for football matches in the South American nation.

According to reports in Argentina, Delhon threw himself under a train in Buenos Aires.

Police confirmed his death mere hours after Burzaco made the claims on a dramatic day in the trial of former South American Football Confederation President and ex-FIFA vice-president Juan Angel Napout, ex-Brazilian Football Confederation head Jose Maria Marin and former Peruvian Football Federation President Manuel Burga.

After Burzaco's testimony - which included claims that he bribed all three officials - prosecutors asked for Burga to be jailed after he was accused of making cut-throat gestures towards the witness during the trial.

Prosecutors claimed Burga was intimidating Burzaco, who became visibly emotional throughout the day and broke down on the stand, with two slicing motions.

Lawyers for Burga denied the allegations, insisting he was "itching his throat" because of dermatitis.

US District Judge Pamela Chen, who is presiding over the case, dismissed suggestions Burga should be jailed but cut access to his phone and computers and placed him under house arrest in Brooklyn.

Burzaco had become increasingly emotional and was holding back tears after his brother, a former law enforcement officer, told him that authorities in Argentina had received “an instruction to shut me down" to “make it possible not to say anything in the US".

"This included killing me," Burzaco testified.

He had earlier claimed that he had paid Burga a total of $3.6 million (£2.7 million/€3.1 million) in bribes.

Marin was paid $2.7 million (£2 million/€2.3 million) and Napout was given $4.5 million (£3.4 million/€3.8 million) in exchange for marketing rights for regional tournaments and matches.

All three deny the charges of racketeering, wire fraud and money laundering.

Burzaco also testified that Brazil's Globo and Mexico's Grupo Televisa had teamed up with a marketing agent to make a $15 million (£11 million/€13 million) bribe to former FIFA senior vice-president Julio Grondona in order to be granted the lucrative rights for the 2026 and 2030 World Cups.

Grondona, the former head of FIFA's Finance Committee who died in 2014, brokered the deal with the two companies, according to Burzaco.

Globo and Grupo Televisa deny any wrongdoing.

Burzaco had testified yesterday that the Argentinian was paid at least $1 million (£760,000/€845,000) in bribes to vote for Qatar to host the 2022 World Cup.

US prosecutors accuse the defendants of participating in schemes involving more than $200 million (£152 million/€173 million) in bribes and kickbacks, both sought and received by officials for marketing and broadcast rights to tournaments and matches.

This includes the major South American tournaments, the Copa América and the Copa Libertadores, as well as the Brazilian domestic tournament Copa do Brasil.

The defendants claim they have been falsely accused, alleging the US Government have relied on the testimony of other FIFA officials, who have cooperated with authorities to reduce their own sentences.

The trial, which is expected to last six weeks, continues today, with Burzaco set to be cross-examined by the defence.