Rail accident rattles Mexico's president succession favorites

The dramatic collapse of a rail overpass in Mexico City that killed at least 24 people has dealt a blow to two of President Andres Manuel Lopez Obrador's most senior aides, who are widely viewed as the leading candidates to succeed him.

Monday night's accident has stirred up concern about the city's infrastructure, in particular Linea 12, the metro line where the collapse occurred, and a flagship project of Foreign Minister Marcelo Ebrard when he was mayor from 2006 to 2012.

Ebrard's name is strongly associated with Linea 12. Its problems have also become a headache for the city's current mayor, Claudia Sheinbaum, who has taken flak for other accidents in the metro system since she took office 2-1/2 years ago. Since opening in 2012, Linea 12 has had a troubled history, suffering disruptions and closures due to technical flaws, as well as allegations of corruption over its construction.

At a Tuesday morning news conference with Lopez Obrador, reporters called on both Ebrard and Sheinbaum to explain how the metro line could have been so unsound, citing complaints and warnings from the public in advance of the disaster. Both politicians said a thorough investigation should be conducted, and urged people to await the findings.

"Whoever acts with integrity should fear nothing," said Ebrard, who has consistently rejected the notion there was any wrongdoing in the building of Linea 12, which he inaugurated in late October 2012, a month before his term as mayor ended. When asked if he was worried that he would be blamed for the accident, Ebrard noted the completed project was only "definitively delivered" to the Mexico City govt in July 2013, several months after he had left office.