MEXICO CITY (AP) — Apple co-founder Steve Wozniak remained hospitalized Thursday in Mexico City following a “health problem” while he was in the city to speak at a business conference, according to a source close to the conference who requested anonymity because they were not authorized to speak about the incident.

Wozniak, 73, had been scheduled to speak at the World Business Forum in Mexico City, a two-day gathering billed as the world’s most important management event. Other advertised speakers were Carly Fiorina, the former CEO of Hewlett-Packard and Muhammad Yunus, a pioneer in microfinance who was awarded the Nobel Peace Prize.

The convivial Wozniak, who teamed up with the late Steve Jobs to found Apple in 1976, had been scheduled as the conference’s closing speaker Wednesday afternoon.

Wozniak suffered the “health problem” shortly before he was scheduled to arrive at the event, the source said, declining to detail what the health problem was.

“At this moment I understand that he is stable,” the source said, adding that the information about his status had come from family members.

The ABC Santa Fe Hospital where Wozniak was taken said it would not provide any information.

Wozniak left Apple in 1985 to pursue a wide range of other interest, but has remained a fervent supporter of the company and a technology evangelist. More recently he has pursued a range of other interests including competing on “Dancing With The Stars” in 2009 and participating as a judge in an online video show called “Unicorn Hunters” that assesses ideas from entrepreneurs vying to build startups potentially worth $1 billion or more.

While dabbling in other startups, Wozniak also has helped keep alive the memory of his longtime friend, Jobs, who died of cancer in 2011.