Campaigning for Afghanistan's presidential election has begun.
The campaign for the successor to Hamid Karzai officially began Sunday for the April 5 poll. Karzai cannot run for a third term under Afghan law.
Analysts cite several strong presidential candidates: former foreign minister Abdullah Abdullah, former finance minister Ashraf Ghani and the president's elder brother, Qayum Karzai.
The election kickoff comes a day after gunmen killed two of Abdullah's campaign workers in the western city of Herat.
Violence threatens the campaign as the Taliban has vowed to disrupt the poll.
The presidential vote will be a crucial test of whether Afghanistan can ensure a stable political transition as NATO combat forces ready their withdrawal after nearly 13 years of war.
Karzai had been expected to sign a bilateral security agreement late last year, which would allow about 10,000 U.S. troops to be deployed in the country after NATO withdraws by December.
However, the Afghan president refused to sign the deal, and has said his successor might now complete negotiations. The delay in signing the deal has strained relations between the U.S. and Afghanistan.