2 US Marines Die in S. Afghanistan Bomb Blasts

U.S. Marines from 2nd Marine Expeditionary Brigade, RCT 2nd Battalion 8th Marines Echo Co. fire a...

U.S. Marines from 2nd Marine Expeditionary Brigade, RCT 2nd Battalion 8th Marines Echo Co. fire a mortar after Marines came under fire, in this July 8, 2009 file photo in Mian Poshteh, Afghanistan. A bomb blast killed two U.S. Marines in Afghanistan's dangerous south, where thousands of American troops have deployed in a massive operation to oust Taliban fighters from the country's opium poppy region, officials said Sunday.

(Joe Raedle/Getty Images)

A bomb blast killed two U.S. Marines in Afghanistan's dangerous south, where thousands of American troops have deployed in a massive operation to oust Taliban fighters from the country's opium poppy region, officials said Sunday.

Some 4,000 Marines moved into Helmand province this month, the largest Marine operation in Afghanistan since the 2001 U.S. invasion. They have met little head-on resistance but remain vulnerable to guerrilla tactics like suicide and roadside bombs.

"These terrorist attacks are hard to prevent, can be carried out by a few individuals, and do not require a military force capable of confronting the Marines," said Arturo Munoz, an expert on the tribal environment in Helmand province with the Washington-based RAND Corp.

"I would expect the Taliban to avoid pitched battles with the Marines in order to avoid a large number of casualties," he said. "This does not mean they will avoid violence."

The two Marines were killed Saturday in Helmand. Military officials did not release any other details nor give a specific location. The military initially reported four Marines had died but later corrected the figure, saying the deaths were mistakenly double-counted.

The American casualties come after eight British deaths in Helmand in a 24-hour period ending Friday, triggering debate in Britain about its role in Afghanistan. Britain has now lost more troops in Afghanistan than in Iraq.

In an interview broadcast Sunday, President Barack Obama called Britain's contribution critically important and said U.S. and British troops face a difficult summer ahead of elections in Afghanistan late next month.

"We've got to get through elections," Obama told Sky News. "The most important thing we can do is to combine our military efforts with effective diplomacy and development, so that Afghans feel a greater stake and have a greater capacity to secure their country."

British Prime Minister Gordon Brown has said fighting the Taliban in Afghanistan will help keep extremist groups from launching attacks inside Britain. And he told Afghan President Hamid Karzai in a telephone call Sunday that Britain would stand "shoulder-to-shoulder with the people of Afghanistan for the long haul," according to a statement by the Afghan presidency.