The NATO-Afghan joint force Sunday mistakenly fired rockets on a civilian shelter killing 12 villagers. Local analysts said civilian casualties will make the ongoing massive crackdown on the Taliban a more challenging task.

Around 15,000 servicemembers with the NATO-led International Security Assistance Force (ISAF) and Afghan National Army soldiers late on Friday launched the biggest ever operation on the Taliban since the United States waged the war on terror in 2001.

The final goal of the mission was believed to be uprooting the Taliban in the central part of the southern Helmand province, the major financial resource of the group.

NATO commanders and the Afghan government said the task is more aimed at resuming the administration, restoring the normal social life and reconstruction of the economy in the region rather than killing Taliban fighters.

To win public confidence and support is the key point of the Operation Moshtarak, ("Together" in English), but Sunday's tragedy would make the rosy result gloomy.

The NATO-Afghan force has surely been in a hard bid to prevent civilian casualties as it gave up a blitz plan and intentionally publicized the offensive more than one week ahead of the Day One.

Some of the 80,000 locals living in Marjah town, the centerpiece of the battlefield, were believed to have been out of town prior to the start of the operation and a number of the insurgents were thought to have fled the area as well.

This helped decrease the casualties but still not enough.

In the town of Marjah, many landmines, roadside bombs and booby- trap were planted to stop the troops' charging. Quite a number of insurgents could have been hiding among residents firing on troops sporadically.

To clear all these obstacles, the civilian casualties were thought to be inevitable and that will put the whole operation in risk of failure.

Foreign troops in Afghanistan have long been criticized for killing civilians and the recent tragedy will not help soothe the public rage.

NATO and Afghan forces carried out large offensives in Helmand province before but failed to secure the central government's authorities. The reason is simple: people do not support those who killed their families and relatives. The Taliban kills, but the troops kill too, they said.

Ahead of the launching of the offensive, Afghan Interior Minister Mohammad Hanif Atmar held a meeting with tribal elders of Marjah and the neighboring district of Nad Ali to woo the public support for the government's future reconstruction plan.

The tribal elders displayed reservation during the meeting, laying the minimization of civilian casualties as the preconditions of their support.

Some analysts feared that as the possible increase of the civilian casualties are doomed, a number of residents might even pick up weapons and fight side by side with the Taliban.

NATO commanders said the Operation Moshtarak were designed for three phases of Shaping, Clearing and Reconstruction.

The most important stage would be the Reconstruction and without the public support, the reconstruction plan will see no chance.

Civilian casualties will not help gain the public support in the war-ravaged nation, analysts said.