José Antonio Abreu, a Venezuelan government economist turned musical educator who created a network of youth orchestras that has been replicated in dozens of countries, died March 24. He was 78.

His death was announced by the Venezuelan newspaper El Universal, where his brother Jesús Abreu is president. No cause was given, but Mr. Abreu had been known to be battling several illnesses since he retired a few years ago from El Sistema, as the musical education program is known.

Mr. Abreu was teacher to generations of Venezuelan classical music performers, most notably Gustavo Dudamel, musical director of the Los Angeles Philharmonic.

“The Venezuelan people that you so loved today are crying for you Maestro,” Venezuelan President Nicolás Maduro said in a statement. “We are comforted by knowing that your legacy will remain alive in the hands and voices of the children of the youth orchestras.”

El Maestro, as Mr. Abreu was almost universally known in Venezuela, was born in the western city of Valera on May 7, 1939, and studied music from an early age. But he initially put his artistic aspirations on hold to become an economist, teaching at two universities in Caracas and later entering politics.

Well into his 30s in 1975, he formed a small orchestra of a dozen young musicians that would become the seed for El Sistema, or the System. Four decades later, the government-financed program claims that it puts 1 million Venezuelan children in contact with classical music through a network of hundreds of youth choirs, orchestras and music centers across the country.

Internationally, its teaching model has spread to more than 60 countries, while its marquee Simón Bolívar Youth Orchestra is a fixture in top-flight concert halls around the world.

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But more recently, the sterling reputations of the institution — and Mr. Abreu — have taken a hit as a result of the program’s close ties to Maduro, whose socialist administration has been accused of undermining Venezuela’s democracy.

In 2014, amid a wave of deadly anti-government unrest, Mr. Abreu and Dudamel appeared alongside Maduro on national TV celebrating a recent European tour and reviewing blueprints for the government-funded “Dudamel Hall” designed by Los Angeles-based architect Frank Gehry.

Around the same time, the book “El Sistema: Orchestrating Venezuela’s Youth” by British musicologist Geoffrey Baker was published, describing Mr. Abreu as a politically cunning, autocratic and vengeful visionary, as much feared as loved. The book also faulted El Sistema as fostering a culture of top-level corruption, favoritism and improper sexual relations between teachers and pupils.

An Associated Press investigation last year found that El Sistema had for more than a decade claimed Mr. Abreu held a doctorate in petroleum economics from the University of Pennsylvania. The school had no record of Mr. Abreu attending, and his brother Jesús Abreu later confirmed to the AP that the doctorate did not exist. He said it had been listed on El Sistema’s website because of an administrative error.

Mr. Abreu never publicly responded to the criticisms as he retired from public view shortly after the book’s publication. But El Sistema disputed Baker’s characterization and Mr. Abreu’s many supporters, including even some government critics, said it overlooked his musical achievements and the successful building of one of the few institutions in Venezuela to have endured almost two decades of polarizing, socialist rule.

As a young musician living in Venezuela during the late 1970s oil boom, arts educator Marshall Marcus was an up-close witness to El Sistema’s birth. In 2012, he established the Sistema Europe, a network of youth ensembles from 25 countries inspired by the Venezuelan model.

He acknowledged that the organization has not evolved as quickly as its track record for musical excellence. But he rejected Baker’s emotionally charged language comparing El Sistema to the mafia and slavery, saying the book might serve only to incense critics who accused Mr. Abreu of being too cozy with the government on which El Sistema’s survival depends.

“It may be an autocracy but it’s one that has allowed thousands of people to flourish,” Marcus told the AP in 2014. “If that’s a tyranny, it sure doesn’t feel like one.”