US forces shot down Iranian drone-Iraq official

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BAGHDAD, March 16 (Reuters) - U.S. forces shot down an Iranian drone aircraft that ventured inside Iraq several weeks ago, a senior Iraqi military official said on Monday, an incident that could highlight deep U.S.-Iranian tensions.

"An unmanned Iranian plane crossed the border and it was discovered by multi-national forces' radar. They intercepted it and brought it down ... an American plane brought it down," Major-General Abdul Aziz Mohammed Jassim, head of military operations at the Iraqi Defence Ministry, told Reuters.

The U.S. military in Iraq has declined comment. It has accused Iran of arming militants and meddling in neighbouring Iraq, where tens of thousands have died in sectarian violence since the U.S.-led invasion to oust Saddam Hussein in 2003.

"According to the report received by multinational forces, this drone entered Iraq mistakenly at a point 100 km (60 miles) from Baghdad. It crossed 10 km (6 miles) into Iraq. It's most likely that its entrance (into Iraq) was a mistake," Jassim said.

Jassim said he could not recall the precise date of the incident, but said it likely took place in late February.

Relations between the government of Iraq's Shi'ite Muslim Prime Minister Nuri al-Maliki and Iran, a fellow majority Shi'ite nation, are mostly friendly.

The two countries fought a bloody eight-year war in the 1980s which killed an estimated 1 million people, but ties have warmed since Saddam, a Sunni Arab, was removed from power.

In recent months, as violence has dropped sharply in Iraq, U.S. officials have spoken less forcefully about Iran's alleged role in Iraq.

In a shift from the Bush administration, U.S. President Barack Obama, who took office in January, has said he would be open to engaging with Iran on a range of issues, from nuclear ambitions to how Iran might assist in Afghanistan.

Iranian President Mahmoud Ahmadinejad has said he also is open to talks with Washington, but demands fundamental changes to U.S. policy in the Middle East.

Underlying U.S.-Iranian tensions is Iran's nuclear programme, which Washington believes is aimed at building atomic weapons. Iran insists it seeks only power generation.

The United States has about 140,000 troops in Iraq, but combat operations will cease by the end of August 2010 under Obama's withdrawal plan, and all U.S. forces are due to leave the country by the end of 2011. (Reporting by Waleed Ibrahim; writing by Missy Ryan)