WRAPUP 8-Three wounded in Myanmar as hundreds of thousands of protesters defy junta

(Adds letter read to rights council in Geneva)

* Fresh demonstrations erupt across Myanmar

* Facebook restricts content run by Myanmar military

* Junta orders release of thousands of prisoners

* U.S. imposes sanctions on military leaders, businesses

Feb 12 (Reuters) - Supporters of ousted Myanmar leader AungSan Suu Kyi clashed with police on Friday as hundreds ofthousands joined nationwide pro-democracy demonstrations indefiance of the junta's call to halt mass gatherings.

The United Nations human rights office said more than 350people, including officials, activists and monks, have beenarrested in Myanmar since the Feb. 1 military coup, includingsome who face criminal charges on "dubious grounds".

The U.N. rights investigator for Myanmar told a specialsession of the Human Rights Council in Geneva that there were"growing reports, photographic evidence" that security forceshave used live ammunition against protesters, in violation ofinternational law.

Special Rapporteur Thomas Andrews urged the U.N. SecurityCouncil to consider imposing sanctions and arms embargoes.

Myint Thu, Myanmar’s ambassador to the U.N. in Geneva, toldthe session that Myanmar did not want "to stall the nascentdemocratic transition in the country," and would continueinternational cooperation.

Friday's mostly peaceful protests were the biggest so far,and came a day after Washington imposed sanctions on generalswho led the takeover.

Three people were wounded when police fired rubber bulletsto break up a crowd of tens of thousands in the southeasterncity of Mawlamyine, a Myanmar Red Cross official told Reuters.

Footage broadcast by Radio Free Asia showed police chargingat protesters, grabbing one and smashing him in the head. Stoneswere then thrown at police before the shots were fired.

"Three got shot – one woman in the womb, one man on hischeek and one man on his arm," said Myanmar Red Cross officialKyaw Myint, who witnessed the clash.

Several people in Mawlamyine were arrested but laterreleased when a thousands-strong crowd stood outside the policestation and demanded they be freed, according to live footagebroadcast by Radio Free Asia.

Doctors have said they do not expect a 19-year-old womanshot during a protest in the capital Naypyitaw on Tuesday tosurvive. She was hit in the head with a live round fired bypolice, witnesses said.

In the biggest city Yangon on Friday, hundreds of doctors inwhite duty coats and scrubs marched past the golden Shwedagonpagoda, the country's holiest Buddhist site, while in anotherpart of town, football fans wearing team kits marched withhumorous placards denouncing the military.