By Nelson Renteria and Michael O'Boyle SAN SALVADOR (Reuters) - A former Marxist guerrilla leader and his conservative rival were locked in an unexpectedly tight race in El Salvador's presidential election run-off on Sunday with the contest too close to call. Polls ahead of the run-off showed Salvador Sanchez Ceren of the ruling Farabundo Marti National Liberation Front (FMLN), the rebel group in the country's 1980-1992 civil war, the favorite to win with about 55 percent support. But he had only a razor-thin lead over his conservative challenger Norman Quijano, the former mayor of San Salvador, with returns in from 98.8 percent of polling stations. Sanchez Ceren had 50.08 percent support against 49.92 percent for Quijano.

KUALA LUMPUR, Malaysia (AP) — Vietnamese searchers on ships worked throughout the night but could not find a rectangle object spotted Sunday afternoon that was thought to be one of the doors of a Malaysia Airlines passenger jet that went missing more than two days ago.

SAN SALVADOR, El Salvador (AP) — Authorities declared El Salvador's presidential runoff election too close to call late Sunday, with just a 0.2-percent margin separating a one-time Marxist guerrilla and the conservative former mayor of El Salvador's capital.