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By Stephanie Nebehay and Emma Farge

GENEVA, Feb 12 (Reuters) - The United Nations SecurityCouncil should consider imposing punitive sanctions, armsembargoes and travel bans on Myanmar because of the militarycoup there, the U.N. human rights investigator for the SoutheastAsian country said on Friday.

Thomas Andrews also said U.N. member states should imposebilateral sanctions and arms embargoes, and ensure that anyassistance goes to aid groups and not to the junta.

"Security Council resolutions dealing with similarsituations have mandated sanctions, arms embargoes, and travelbans, and calling for judicial action at the InternationalCriminal Court or ad hoc tribunals. All of these options shouldbe on the table," Andrews told the U.N. Human Rights Council.

There were "growing reports and photographic evidence" thatMyanmar security forces have used live ammunition againstprotesters, he said.

"This violence violates international law," he said.

The 47-member Geneva forum is holding a special session atthe request of Britain and the European Union to consider aresolution calling for the release of ousted Myanmar leader AungSan Suu Kyi, and for Andrews and other U.N. monitors to visit.

Supporters of Suu Kyi clashed with police on Friday ashundreds of thousands joined nationwide pro-democracydemonstrations in defiance of the junta's call to halt massgatherings.

"Myanmar's democratically elected political leadership,including Aung San Suu Kyi and President U Win Myint, have beendetained on politically motivated charges," said Nada al-Nashif,deputy U.N. High Commissioner for Human Rights.

More than 350 political and state officials, activists andcivil society members, including journalists, monks and studentshave been taken into custody, she said, adding: "Several facecriminal charges on dubious grounds."

Myint Thu, Myanmar's ambassador to the U.N. in Geneva, saidMyanmar would maintain cooperation with the U.N. and Associationof Southeast Asian Nations (ASEAN) and uphold internationalhuman rights treaties.

"We do not want to stall the nascent democratic transitionin the country," Myint said.(Writing by Stephanie Nebehay; Editing by Timothy Heritage)