Mexico's Presidential Elections - Too close to call

The specter of political chaos hung over Mexico's young democracy on Monday after two rival presidential candidates both claimed victory in a bitter election that divided the country between left and right.

Election officials said the race was too close to declare a winner and a recount was needed, but that didn't stop combative left-winger Andres Manuel Lopez Obrador and ruling party conservative Felipe Calderon from insisting they had won.

Rival celebrations erupted just a few miles apart in the early hours of Monday morning, including thousands of people in Mexico City's vast central square.

It could be days before a final vote count is in, and some feared Mexico could be lurching toward a nightmare scenario of political deadlock, street protests and volatility in financial markets.