KABUL, Afghanistan >> Seven U.S. service members were killed today in two separate roadside bomb attacks in southern Afghanistan, NATO said.

No details were given of the attacks, although eyewitnesses in the southern city of Kandahar said an armored U.S. Army Humvee hit a roadside bomb in the early afternoon. Several bodies were seen being removed from the vehicle, which was set on fire by the blast.

The deaths bring to 14 the number of U.S. troops killed in action in eastern and southern Afghanistan over the past three days.

A spike in U.S. troop numbers in Afghanistan to over 120,000 has brought increased contact with insurgents and a rising death toll. Forty-nine U.S. service members have died in Afghanistan this month, still fewer than the 66 killed in July.

To the east in Nangarhar province, the head of Lal Pur district, Syad Mohammad Palawan, was killed when a bomb planted on his vehicle exploded as he was driving into a government compound to attend a meeting of provincial security and political leaders, said police spokesman Ghafor Khan.

Insurgents apparently planned for the bomb to explode inside the compound in the provincial capital Jalalabad where it could potentially have caused far greater destruction, Khan said.

Three of Palawan’s bodyguards were wounded, Khan said, while the Interior Ministry put the figure at five.

The attack followed a failed assault on two coalition bases in nearby Khost province Saturday, in which more than 30 insurgents were killed. The attacks indicate that militant activity is rising in parts of the east, as coalition forces focus resources on Kandahar and other Taliban strongholds in the south.

Security in eastern Afghanistan is critical because the region includes the capital, Kabul, which the insurgents have sought to surround and isolate from the rest of the country. Jalalabad also lies just 35 miles west of the Pakistan border, where militants maintain safe havens from which to plan attacks and infiltrate foreign fighters linked to al-Qaida across the rugged mountains.

Shutting down such sanctuaries has been a key demand of the government of President Hamid Karzai, who on Saturday renewed his criticism of coalition strategy in fighting Afghanistan’s stubborn insurgency — part of a pattern of greater outspokenness by the Afghan leader as he appeals for support among the beleaguered Afghan public.

In a meeting with visiting German Parliament Speaker Norbert Lammert, Karzai said there was a “serious need” to alter strategy against the Taliban and other groups linked to al-Qaida, the presidential office said.

“There should be a review of the strategy in the fight against terrorism, because the experience of the last eight years showed that the fight in the villages of Afghanistan has been ineffective apart from causing civilian casualties,” Karzai was quoted as saying in a news release.