Juan Ángel Napout, the former president of South American football’s governing body (Conmebol) and José Maria Marin, the former president of Brazil’s football federation were both found guilty of racketeering and wire fraud conspiracies following a five-week trial in New York City.

A verdict on their co-defendant, Manuel Burga, the former head of football in Peru, is pending.

The convictions add to the 23 guilty pleas prosecutors have already been secured against individuals and entities accused of bribery in the government’s sprawling investigation of corruption at football’s governing body, Fifa.

Over 40 people and companies have been charged as part of the investigation, which the US attorney’s office says remains ongoing. The case was the first to come to trial since a dramatic dawn raid at a hotel near Fifa headquarters in Zurich revealed the investigation to the public for the first time.

The trial, which lasted five weeks and saw 28 witnesses testify for the prosecution, revealed a web of corrupt practice that prosecutors say spanned several decades and resulted in at least $150m in bribes.

The bribes were paid to the defendants in exchange for the rights to the region’s premier tournaments including the Copa América and the Copa Libertadores.

During closing arguments US prosecutors totaled the amounts each of the defendants had been owed in bribes between 2010 and 2016. Napout’s was a total of $10.5m, Marin’s $6.5m and Burga’s $4.4m.

All three were charged with racketeering conspiracy, with Napout and Marin now convicted as Burga’s case remains before the jury. Napout was also convicted on two counts of wire fraud conspiracy in relation to the Copa América and Copa Libertadores bribery schemes.

Marin – who was also accused of taking bribes for the rights to the Copa do Brasil, Brazil’s domestic knockout tournament – was convicted on six counts in total.

None of the three men called any witnesses in their defence. Although lawyers for each acknowledged the bribery schemes had existed, they claimed their clients had not been part of it and described the charges as government overreach.

The verdict will be seen as a stunning success for prosecutors, whose years-long investigation sent shockwaves around the world of international soccer.

The trial saw a host of former soccer executives and sports marketers testify against their former colleagues.

Alejandro Burzaco, the government’s star witness and the former CEO of an Argentine media company that paid millions in bribes gave four days of evidence accussing all three men of taking multiple illicit payments.

Burzaco estimated he had paid $160m in bribes throughout his career to dozens of officials in exchange for broadcast and marketing rights. The former CEO also told the court he was aware that Julio Grondona, formerly Sepp Blatter’s number two at Fifa until his death in 2014, had taken at least $1m in exchange for his vote for Qatar to host the 2022 World Cup.

The Argentine also alleged that some of the world’s top broadcasters he had parterned with, including TV Globo in Brazil and Fox Sports in America, were complicit in some bribe payments. Both companies deny the allegations.

The trial unfolded under heightened security at a federal courthouse in Brooklyn amid concerns over witness intimidation.

Burga, the defendant still awaiting a verdict, was accused by prosecutors of making throat slitting gestures towards Burzaco during his testimony. Burga denied the allegations through his lawyer.

After the guilty verdicts were read on Friday afternoon, Judge Pamela Chen ordered Napout, 59 and Marin, 85, be remanded in custody before sentencing as both were deemed flight risks.

As the order was made, three plainclothes US Marshal officers unveiled their badges and entered the court and surrounded both men, who appeared stunned at the officer’s presence.

A spokesperson for Fifa said the association would now “seek restitution and recover any losses caused” as a result of the two men’s conduct while in office.