A U.S. paratrooper and a British soldier were killed in separate attacks Saturday in eastern and northern Afghanistan, officials said.

The American was killed when his patrol came under fire in the volatile eastern province of Khost, a U.S. military statement said. U.S. forces responded with small-arms fire, artillery and air attacks, chasing off the insurgents. It was not immediately clear if any of the assailants were killed.

In the north, gunmen attacked NATO-led peacekeepers as they patrolled the city of Mazar-e Sharif, killing the British soldier and wounding five others, Britain's Defense Ministry said.

Security forces cordoned off the area and arrested four suspects, said Capt. Michele Cortese, a spokesman at the NATO force's headquarters in Kabul, the Afghan capital.

Mazar-e Sharif has been considered relatively secure because loyalists of the Taliban militia, which was ousted from power in Afghanistan by a U.S.-led invasion in late 2001, are not believed to operate there. So it was not immediately clear what motivated the attack.

Violence during the last week has killed 23 people, including 14 suspected insurgents and two worshipers who were dragged from a mosque and shot. The incident underlined the challenges of bringing stability and strengthening Afghanistan's fledgling democracy.

Meanwhile, election organizers announced that they planned to release the final list of newly elected legislators from a Sept. 18 vote in the next few days, said Aleem Siddique, a spokesman for the election commission. The announcement has been delayed by allegations of widespread fraud that undermined the vote's legitimacy.

Human rights advocates warn that at least half of those listed as provisional winners are former warlords or others still linked to armed groups responsible for much of the violence during the country's quarter-century of war.

A British soldier patrols Mazar-e Sharif where gunmen attacked NATO troops.