Police in Myanmar have fired rubber bullets during a demonstration in the capital Nay Pyi Taw, as thousands defied a ban on protests.
Water cannon and tear gas have also been used against protesters, but reports of live bullet usage are unconfirmed.
One woman is in hospital in a critical condition with a head wound.
Protesters are standing against a military coup that removed the elected government last week.
It is the fourth day of consecutive protests. A ban on large public gatherings and night-time curfews has been instigated in some cities, with military leader Min Aung Hlaing warning that no-one is above the law.
The demonstrators have been demanding the release of elected leader Aung San Suu Kyi, along with senior leaders of her National League for Democracy Party (NLD). She was arrested when the military seized power.
The army has declared a year-long state of emergency and claimed, without evidence, that an earlier election was fraudulent.
One protester, 18-year-old Nelly (not her real name), described the situation outside her house in Yangon.
“There are hundreds of people protesting against the military coup. Everything is in total chaos,” she told BBC Outside Source on World Service radio.
“Yesterday [Monday] I went in front of the UN [to protest]. Today I didn’t go because the situation is really dangerous.
“My biggest fear is our safety, because there are lots of people on the roads protesting but there is also a lot of violence from police officers. We don’t know when we’ll be shot at or when they will arrest us.”
How did the situation escalate?
Earlier on Tuesday, police began using water cannon against protesters in Nay Pyi Taw.
But the crowd withstood the barrage of water fired at them and refused to retreat, according to Reuters news agency.
“End the military dictatorship,” people yelled.
Warning shots were eventually fired into the air, before rubber bullets were fired at protesters.
According to BBC Burmese, who spoke to an unnamed medical officer from a Nay Pyi Taw hospital, two protesters were injured. A woman was seriously hurt from a head wound and another demonstrator had chest injuries. It is not yet clear how exactly they were wounded.
Reuters news agency also spoke with a doctor who said X-rays indicated live ammunition had been used against the woman with critical head injuries.
The United Nations condemned the use of heightened force. “The use of disproportionate force against demonstrators is unacceptable,” said Ola Almgren, the UN resident co-ordinator and humanitarian coordinator in Myanmar, also known as Burma.
In its first acknowledgement of the protests, Myanmar’s state TV channel said on Tuesday that police had acted legally, and that some had been injured trying to disperse protesters. It reported that a police truck had been destroyed at a protest in the city of Mandalay.
There have been numerous unconfirmed reports of police officers crossing over to join protesters. In some areas, police also allowed demonstrators through their barricades.
The BBC’s South East Asia correspondent Jonathan Head said it was clear officers were making a “more determined effort” to disperse protesters.
Previous protests against the country’s decades-long military rule, in 1988 and 2007, saw demonstrators killed.
What are protesters saying?
“We come here well aware of the ban over gatherings of more than five people,” one young male protester told BBC Burmese, as he gathered with others near a UN building in Yangon in a bid to boost international attention. “However, we come out because we have to protest until the president and Mother Suu are freed,” he added, referring to leader Aung San Suu Kyi, who has not been heard from since being placed under house arrest.
A female protester, who also did not want to be named, said: “Young people have their future, so we can’t tolerate this… We will keep on fighting until we get our president and Mother Suu back, whatever it takes.”
She said young protesters wanted to avoid confrontations with military, as had been seen in the past.
Even though Ms Suu Kyi’s record on human rights has previously been criticised internationally, she remains very popular in the country. Her win in the 2020 election was confirmed by various overseas monitoring bodies.
How is the military reacting?
On Monday, Gen Min Aung Hlaing gave his first televised address since the coup a week earlier. He insisted the seizure of power was justified due to “voter fraud”, accusing the electoral commission of failing to investigate irregularities over voter lists in November’s election.
The commission had said there was no evidence to support claims of widespread fraud.
Ms Suu Kyi and various senior leaders from the NLD, including President Win Myint, were detained on 1 February.
Gen Min Aung Hlaing promised new elections overseen by a new “reformed” election commission, and said the military would hand power to the winner.
He also said his rule would be “different” from what was effectively a 49-year military grip on power that ended in 2011.
He spoke of achieving a “true and disciplined democracy”, a phrase that drew scorn from some opponents of the coup on social media.
On Tuesday, New Zealand announced that it would be suspending all high-level contact with Myanmar and imposing a travel ban on its military leaders.
Prime Minister Jacinda Ardern also said there would be restrictions on aid that benefited the military.
It is the first major international move to isolate the military since they took power.