Dhaka, Bangladesh (CNN) -- Hundreds of Muslims fleeing sectarian violence in Myanmar tried to enter Bangladesh on Wednesday, but many were turned away by the authorities.
Bangladesh has reinforced its border with Myanmar, amassing border guards and coast guards who were keeping watch on the River Naf, where rickety fishing boats were filled with Rohingyas, ethnic Muslims from Myanmar's Rakhine State.
Bangladeshi Foreign Minister Dipu Moni on Wednesday said her country was not willing to give shelter to Rohingya refugees, despite international calls for opening the border to people fleeing the clashes between Muslims and Buddhists in western Myanmar.
"We're already burdened with thousands of Rohingya refugees staying in Bangladesh and we don't want anymore," she said.
The Office of the U.N. High Commissioner for Refugees and human rights groups have urged Dhaka to open the border.
The police and witnesses said dozens of fishing boats carrying mostly women and children were crossing the Naf. They said many people were severely injured and many had not eaten for days while drifting on the river waiting for opportunities to try to get into Bangladesh.
Maj. Shafiqur Rahman, a deputy commanding officer of the Bangladesh Border Guard in Teknaf, said his guards detained at least 110 people from Myanmar on Wednesday.
During the latest unrest in Rakhine, which began last week, more than 21 people have been killed, according to Myanmar state media.
The government has imposed a state of emergency in the embattled areas to try to bring the situation under control.
The unrest began after the police in Rakhine detained three Muslim men in relation to the rape and killing of a Buddhist woman late last month. That was followed by an attack on a bus in early June in which 10 Muslim people were killed.
The U.S.-based Human Rights Watch has urged the Myanmar authorities to take all necessary steps to protect communities at risk in Rakhine.
"The government has taken inadequate steps to stop sectarian violence between Arakan Buddhists and ethnic Rohingya Muslims, or to bring those responsible to justice," Human Rights Watch said in a statement this week.
The violence in Rakhine "is spiraling out of control under the government's watch," said Elaine Pearson, deputy Asia director at Human Rights Watch.
The Bangladesh border guards said they had sent back more than 1,000 Rohingya Muslims in the past several days.
Bangladesh has put troops on high alert along the 200-kilometer border with Myanmar, said Shamsul Haque, Bangladesh's state minister for home affairs.
Bangladeshi officials estimate 300,000 Rohingya Muslims live in the country, with about a tenth of them in two official refugee camps in the southern district of Cox's Bazaar.
The Rohingya, who have long sought refuge in other countries, say they have been persecuted by the Myanmar military over the years.