Police cracked down in Myanmar on Saturday to prevent opponents of military rule gathering and one woman was shot and killed, media reported, after the country's United Nations envoy urged the U.N. to use "any means necessary" to stop a Feb. 1 coup.

Myanmar has been in turmoil since the army seized power and detained elected leader Aung San Suu Kyi plus much of her party leadership, alleging fraud in a November election her party won in a landslide.

Uncertainty has grown over Suu Kyi's whereabouts, as the independent Myanmar Now website on Friday quoted officials from her National League for Democracy (NLD) party as saying she had been moved this week from house arrest to an undisclosed location.

The coup has brought hundreds of thousands of protesters to Myanmar's streets and drawn condemnation from Western countries, with some imposing limited sanctions.

Police were out in force in the main city of Yangon and elsewhere on Saturday, taking up positions at usual protest sites and detaining people as they congregated, witnesses said. Several media workers were detained.

Three domestic media outlets said a woman was shot and killed in the central town of Monwya. Police there were not immediately available for comment.

Earlier, a protester in the town said police had fired a water cannon as they surrounded a crowd.

"They used water cannon against peaceful protesters; they shouldn't treat people like that," Aye Aye Tint told Reuters from the town.

In Yangon, despite the police presence, people came out to chant and sing, then scatter into side streets as police advanced, firing tear gas, setting off stun grenades and firing guns into the air, witnesses said.

Similar scenes played out in the second city of Mandalay and several other towns, including Dawei in the south, witnesses and media said.

Among those detained at a Mandalay protest was Win Mya Mya, one of only two Muslim members of parliament for the NLD, media said.

Junta leader General Min Aung Hlaing has said authorities were using minimal force. Nevertheless, at least three protesters have died in the weeks of turmoil. The army says a policeman was also killed.

'Prevail'

At the U.N. General Assembly, Myanmar's Ambassador Kyaw Moe Tun said he was speaking on behalf of Suu Kyi's government and appealed for "any means necessary to take action against the Myanmar military and to provide safety and security for the people."

"We need further strongest possible action from the international community to immediately end the military coup ... and to restore the democracy," he said.

Kyaw Moe Tun appeared emotional as he read the statement on behalf of a group of elected politicians that he said represented the legitimate government.

Delivering his final words in Burmese, the career diplomat raised the three-finger salute of pro-democracy protesters and announced, "Our cause will prevail."

Reuters was not immediately able to contact the army for comment.

Coup opponents hailed Kyaw Moe Tun as a hero and flooded social media with messages of thanks. U.N. Special Rapporteur Tom Andrews said he was overwhelmed as he watched the ambassador's "act of courage."

"It's time for the world to answer that courageous call with action," Andrews said on Twitter.

China's envoy did not criticize the coup and said the situation was part of Myanmar's "internal affairs." China supports diplomacy by southeast Asian countries, he said.

In more bad news for the generals who have traditionally shrugged off outside pressure, Australia's Woodside Petroleum Ltd said it was cutting its presence in Myanmar over concern about rights violations and violence by security forces.

"Woodside supports the people of Myanmar and we hope to see a peaceful journey to democracy," the company said.

'Loss of rights'

A lawyer for Suu Kyi, Khin Maung Zaw, told Reuters he had also heard that she had been moved from her home in the capital, Naypyitaw, but could not confirm it. Authorities did not respond to a request for comment.

The lawyer said he had been given no access to Suu Kyi ahead of her next hearing on Monday and he was concerned about her access to justice and legal counsel.

Nobel Peace laureate Suu Kyi, 75, spent nearly 15 years under house arrest during earlier military rule. She faces charges of illegally importing six walkie-talkie radios and of violating a natural disaster law by breaching coronavirus protocols.

The army has promised an election but not given a date. It has imposed a one-year state of emergency.

The question of an election is at the center of a diplomatic effort by the Association of Southeast Asian Nations, of which Myanmar is a member.

Indonesia has taken the lead but coup opponents fear the effort could legitimize the junta and what they see as its bid to annul the November election.