Had earlier rebuked country's leaders for delaying peace efforts.
Bags over 60 percent votes to knock out the opposition in first round.
Ethiopia strongly condemns cross-border raids.
Nervous soldiers opened fire on vehicle, prompting protests.
Attackers said to be members of South Sudanese tribe.
by Erin Wright On the second anniversary of Boko Haram's kidnapping of hundreds of schoolgirls, the mood seems rooted in a sort of resigned despair.
Amnesty International calls for full forensic probe.
Riek Machar returned to his country after two years.
Effectively ends global effort to pursue justice after Kenya election violence.
Skeptics say the controversial leader made such promises in the past.