A new elevated bike path that was heralded as a top legacy project of the Rio de Janeiro Olympics collapsed Thursday, killing at least two people.

The accident on the Tim Maia bike path was the latest in a series of problems besetting preparations for the Aug. 5-21 games, which include worries about an outbreak of the Zika virus, political turmoil that threatens to topple President Dilma Rousseff, underwhelming ticket sales and budget cuts amid Brazil's worst recession in decades.

Municipal Secretary Pedro Paulo Carvalho said a third person was thought to be missing after a giant wave apparently swept up a rocky cliff, lifted an approximately 50-meter stretch of the bike path and sent it plunging onto the rocks and sea below.

Rio's fire department confirmed only the two deaths. Local news media said two other people were rescued alive.

Helicopters fished the two who died out of the water and laid them out on the golden sands of Sao Conrado beach. Initially covered by colorful beach sarongs, they were later shrouded by a sheet of black plastic.

The bodies were left on the sand for hours, and waves periodically washed over them. A crowd of beachgoers gathered around the corpses, while others continued a game of beach soccer nearby. Thursday was a public holiday in Brazil, and with the weather sunny and warm, the city's bike paths, beaches and other outdoor recreational spots were packed.

Joao Ricardo Tinoco identified one of the victims as his brother-in-law, Eduardo Marinho Albuquerque. He said the 54-year-old father of one was out jogging at the time of the accident. Tinoco's sister, Eliane, kneeled over the body, kissing his face and begging to be given another moment to "say goodbye" to her husband.

Carvalho said it was too early to tell what caused the accident and said an investigation was underway.

Shoddy construction is a perennial problem in Brazil, where graft is a fixture of many construction projects.

"It's clear that an accident like this is unpardonable," Carvalho told the Globo television network.

The entire 2.5-mile bike path, which links the tony beachfront neighborhoods of Sao Conrado and Leblon, is now closed, he said.

Rio Mayor Eduardo Paes, who was in Greece for the lighting of the Olympic torch, was quoted in a statement as also calling the accident "unpardonable," and saying he was flying back to Rio immediately to follow the investigations into its causes.

When the structure was inaugurated, Paes hailed it as "the most beautiful bike path in the world."

The respected newspaper O Estado de S. Paulo reported that the company that built the bike path is owned by the family of the municipal public works secretary, Antonio Paulo Viegas Figueira de Mello. The report said Concremat was founded by Mello's grandfather, Mauro Viegas.

A spokeswoman for the company declined to comment on the alleged family connection. She also declined to provide any details about the bike path and could not say whether the company was involved in any other Olympic projects. Concremat's website was down on Thursday.

"The priorities at the moment are to ensure treatment of the victims and their families and evaluate the causes of the accident," said the company's two-sentence statement.

The bike path is perched high above the water on concrete and metal pillars set into a rocky cliff. Inaugurated on Jan. 17 with much fanfare, the 45 million-real ($12.5 million) project was initially heralded as one of the most successful Olympic legacy projects, earning kudos for its spectacular views. But soon detractors began to complain that the brand-new structure was already showing signs of deterioration and that the narrowness of the path made cyclists easy prey for muggers.

The bike path runs parallel to a road high above the sea that will be used for the road-cycling event in the Olympics. Construction is under way to extend the bike path westward to the Barra da Tijuca neighborhood that is one of the Olympic hubs and Carvalho said engineering of that stretch would face extra scrutiny. The Concremat spokeswoman said the company was not building the extension.

In an emailed statement, Rio's Olympic organizers said "our thoughts and sympathies are with the people and their families and friends affected by the tragic accident."

The collapse happened just hours after the flame for South America's first Olympics was kindled at the Greek birthplace of the ancient games. The flame begins a 15-week journey that will culminate with the Aug. 5 opening ceremony in Rio.