Anja Niedringhaus and Kathy Gannon
Anja Niedringhaus (left) was killed and Kathy Gannon was injured when an Afghan policeman opened fire in eastern Afghanistan Getty / Twitter

A veteran photographer for Associated Press (AP) has been shot dead and a long-serving journalist for the news agency has been wounded in eastern Afghanistan by an Afghan policeman.

The injured journalist was named as experienced Canadian-born Pakistan and Afghanistan correspondent Kathy Gannon by the Canadian Embassy in Kabul.

She was wounded twice and is receiving medical attention, according to AP. She was described as being in stable condition and talking to medical personnel.

Internationally acclaimed German photographer Anja Niedringhaus, 48, was named as the journalist killed.

The two were in a police station the remote small town of Khost on the Afghanistan border with Pakistan when the incident took place.

"Anja and Kathy together have spent years in Afghanistan covering the conflict and the people there. Anja was a vibrant, dynamic journalist well-loved for her insightful photographs, her warm heart and joy for life. We are heartbroken at her loss," said AP Executive Editor Kathleen Carroll, speaking in New York.

They had been reporting from the Tanay district in Khost province with an official from the Independent Election Commission when the attack took place, an interior ministry source told the BBC.

"Naqibullah, a policeman in Tani district of Khost, opened fire on two foreign journalists. One was killed and one was wounded," a spokesman for the governor of Khost province, Mobariz Zadran, told Reuters.

According to an AP freelancer who witnessed the attack, the two had arrived in the heavily guarded district compound before the incident:

As they were sitting in the car waiting for the convoy to move, a unit commander named Naqibullah walked up to the car, yelled "Allahu Akbar" — God is Great — and opened fire on them in the back seat with his AK-47. He then surrendered to the other police and was arrested.

The shooting came as Afghanistan increases security ahead of presidential elections in response to threats of violence by the Taliban.

The new president will succeed Hamid Karzai who has been in power since 2001.

Nearly 200,000 troops have been deployed across the country to prevent terrorist attacks.

Afghanistan's Interior Minister Umer Daudzai said on Thursday that the election will take place in a "secure environment".