A security guard in Afghanistan shot dead two foreigners who worked for the Germany-based shipping company DHL on Saturday.

The shooting took place outside of the company's Kabul location, across from the Iranian embassy and near Afghanistan's security service. The shooter killed a British citizen and a South African, officials for the two governments said.

After killing the DHL's country director in Afghanistan and his deputy, the gunman killed himself.

Officials said he opened fire when the DHL workers entered the company's compound in their vehicle, where the gunman also worked as a security guard.

Mirza Mohammad Yarmal, an Interior Ministry official, told The Associated Press that the gunman had only worked at the site for about a month. Police had no evidence linking the man to insurgent or Taliban groups.

Gerold Beck, a DHL spokesperson, told AP the company was working with authorities to "clarify the situation."

Following the incident, Afghan police arrested 13 people, including DHL guards and employees, said Interior Ministry spokesperson Zemeri Bashary.

The Taliban took immediate responsibility earlier this week for the shooting death of another foreign worker, a dual British and South African citizen.

Although the latest shooting may not be connected to anyone other than the gunman, international security companies warned their clients about intelligence that suggests militants may target restaurants catering to Westerners.

Meanwhile, Turkey confirmed on Saturday that three of its nationals working in Afghanistan were kidnapped in the eastern province of Khost Thursday. Two aid workers from Bangladesh were also kidnapped in the province of Ghazni on the same day.

The Taliban killed three female foreign aid workers, including two Canadians, near Kabul in August.

With files from The Associated Press