KABUL: Militants in eastern Afghanistan attacked U.S. forces with gunfire Sunday after a roadside bomb hit their convoy. Three American troops died in the attack, officials said.

July was the deadliest month for international troops since the 2001 U.S.-led invasion, but August has gotten off to a lethal start.

The three U.S. deaths Sunday bring to nine the number of NATO troops killed already this month, after six NATO troops died on Saturday. Six of the nine were American.

Last month, 74 foreign troops were killed, including 43 Americans.

A record 62,000 U.S. troops are now in Afghanistan, more than double the number in the country a year ago. President Barack Obama has increased the U.S. focus on Afghanistan, even as the Pentagon begins pulling troops out of Iraq. Other NATO countries have some 39,000 troops in Afghanistan.

"We have a lot more troops in country. We have a lot more operations ongoing, and it increases our contact with the enemy, and that unfortunately results in an increase in casualties," said Lt. Cmdr. Christine Sidenstricker, a U.S. military spokeswoman.

Sidenstricker said she could release no more details about Sunday's attack, including the province in eastern Afghanistan in which it occurred. Military officials still had to inform family members of the deaths, she said.

Three U.S. troops were killed Saturday in southern Kandahar province when roadside bombs ripped through their patrol, while a French soldier died in a gunbattle north of the capital. Two other NATO troops were killed on Saturday, NATO announced on Sunday, but the troops' nationalities were not immediately released.

Roadside bombs have become the militants' weapon of choice in Afghanistan, and the number of such attacks has spiked this year. U.S. troops say militants are now using bombs with little or no metal in them, making them even harder to detect. Militants are also planting multiple bombs on top of one another and planting several bombs in one small area.

U.S. commanders have long predicted a spike in violence in Afghanistan this summer, the country's traditional fighting season, and Taliban militants have promised to disrupt the country's Aug. 20 presidential election. Heavy violence in the country's south could close scores of polling stations, calling into question the legitimacy of the vote if a large percentage of southern Afghans are kept from voting. LINK