KABUL, Afghanistan - Afghan authorities Monday announced the arrests of seven people in last week's suicide car bombing that killed six NATO soldiers including four colonels - three of them American and one Canadian.

The blast was the first in a series of major Taliban attacks against NATO targets - the insurgents' apparent response to a planned NATO offensive in the south and peace overtures by the Afghan government.

Altogether, 18 people were killed in the blast Tuesday near the destroyed Afghan royal palace, the deadliest attack against coalition forces in the Afghan capital in eight months. The car bombing was followed a day later by a ground assault against the U.S.-run Bagram Air Field north of Kabul, and Saturday's attack on the giant Kandahar Air Field, the biggest NATO base in southern Afghanistan.

The spokesman for Afghanistan's intelligence service, Saeed Ansari, said the seven suspects were taken into custody separately over the last week.

Ansari said the seven were under the command of the Taliban's "shadow governor" of Kabul, Daoud Surkha, who the Afghans allege is hiding in Pakistan. He said the cell was responsible for at least seven other attacks in the capital since last year, including the February assault against guesthouses frequented by foreigners in which six Indians were killed.

Previously, Ansari said the February attack was carried out by the Pakistan-based insurgent group Lashkar-e-Taiba, which India blames for the 2008 Mumbai attacks that killed 166 people.

"We are saying that they have been trained on the other side of the border, so it is clear that the intelligence service of our neighboring country has its role in the training and supporting of this terrorist group," he said, in a clear reference to Pakistan's Inter-Services Intelligence Agency, which maintained close ties to the Taliban years ago.

Taliban fighters still use the lawless areas along Pakistan's border with Afghanistan as a sanctuary despite Pakistani military operations and U.S. drone attacks.

In Islamabad, Pakistan Foreign Ministry spokesman Abdul Basit called the allegation of involvement by his country's intelligence service "baseless and groundless."

The recent attacks in Kabul and against the bases appeared to be the Taliban's response to NATO's plans for a major operation in the coming weeks in the Taliban southern stronghold of Kandahar, and an attempt at demonstrating that the insurgents are capable of pressuring the coalition in several parts of the country.

Sixteen insurgents and one U.S. contractor were killed in the Bagram attack. NATO says a number of coalition soldiers were wounded in the Kandahar attack but gave no precise figures.

In the latest fighting, the Canadian Ministry of Defense announced that a 26-year-old Canadian soldier was killed Monday by a roadside bomb in southern Afghanistan.

Recent insurgent assaults also seemed to be a rebuff to President Hamid Karzai's plans to offer peace to extremists willing to give up the fight. Karzai plans to roll out a program of jobs, training, and financial help to insurgents willing to give up during a national conference, or peace jirga, set for June 2.

Afghan Forces Now Top Iraq's

More U.S. forces are serving in Afghanistan than in Iraq, the Pentagon said Monday - a first since the 2003 U.S. invasion of Iraq and a reflection of the new primacy of the nine-year Afghan war.

The Pentagon said that 94,000 U.S. forces were

now in Afghanistan and 92,000 in Iraq. The numbers are expected to rise in Afghanistan and fall in Iraq as the Obama administration shifts focus to what it has called the more important conflict.

U.S. forces in Afghanistan will reach about 98,000 this summer. At the height of the Iraq war in 2006-07, the United States had from 130,000 to 172,000 forces fighting there.

All U.S. combat forces are to leave Iraq by September, and the United States and Iraq have agreed that no U.S. forces will remain in the country by 2012.

The White House said the plans to deploy 98,000 troops in Afghanistan did not represent an absolute ceiling, but few expect Obama to approve any large escalation beyond that number. He has pledged to begin bringing U.S. forces home from Afghanistan in July 2011.

- Associated Press

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