Afghans head to the polls in the third presidential elections to be held since the fall of the Taliban in 2001.
A massive security operation is under way to thwart the Taliban which has vowed to disrupt the election.
Eight candidates are vying to succeed Hamid Karzai, who is barred by the constitution from seeking a third consecutive term as president.
The poll has already been overshadowed by the shooting of two journalists.
An Afghan police officer has shot dead a foreign photographer and badly injured another in the country\’s violent east.
One of the women, Anja Niedringhaus, died in the attack. Her colleague, Kathy Gannon, is reported to be stable.
The attack took place in the town of Khost near the border with Pakistan.
Authorities say the police officer was arrested following the incident inside a police compound in the eastern province of Khost.
The dead journalist was identified as 48-year old Anja Niedringhaus, an awarding winning German photographer who was working for the Associated Press. AP reporter Kathy Gannon was in stable condition after being wounded twice.
It was the third deadly attack against journalists in the past three weeks as violence has increased in the run-up to Saturday\’s national and local elections.
The Taliban has vowed to disrupt the upcoming vote.
Nearly 200,000 troops have been deployed across the country to prevent attacks.
Rings of security have been set up around each polling centre, with the police at the centre and hundreds of troops on the outside.
Reporting restrictions are in place, limiting what can be broadcast about the candidates.
If nobody wins more than 50% of the vote, a run-off election will be necessary.
There are eight candidates for president, including former foreign ministers Abdullah Abdullah and Zalmai Rassoul, and former Finance Minister Ashraf Ghani Ahmadzai.
On March 11, British-Swedish radio journalist Nils Horner was shot dead at point-blank range on the streets of Kabul. Nine days later, gunmen shot and killed Afghan reporter for the French News agency Sardar Ahmad, as well as his wife and two of his three young children in Kabul\’s heavily protected Serena Hotel.
On Thursday, Jan Kubis, the United Nations Special Representative for Afghanistan, urged Afghan citizens not to let anyone deprive them of their right to vote.
Kubis said there might be difficulties and security problems, but Afghanistan is much better prepared for Saturday\’s election than it was in 2009.
The Taliban has claimed responsibility for recent election-related violence, including Tuesday\’s suicide bombing outside the Afghan Interior Ministry, killing at least six police officers.
Source – Agencies