They had large banners urging Myanmar to "talk to us about citizenship and Rohingya ethnicity".

Some 200,000 Rohingya rallied in a Bangladesh camp Sunday to mark two years since they fled a violent crackdown by Myanmar forces, just days after a second failed attempt to repatriate the refugees.

During the brutal August 2017 offensive, around 740,000 of the Muslim minority escaped Myanmar's Rakhine state -- joining those who had fled earlier persecution.

A total of nearly one million refugees now live in three dozen squalid camps in Bangladesh's southeastern border district of Cox's Bazar.

On Sunday, children, hijab-wearing women, and men in long-skirt lungis shouted "God is Great, Long Live Rohingya" as they marched at the heart of the world's largest refugee camp to commemorate what they described as "Genocide Day".

Under the scorching sun, thousands joined in a popular song with the lyrics "the world does not listen to the woes of Rohingya".

"I have come here to seek justice for the murder of my two sons. I will continue to seek justice until my last breath," 50-year-old Tayaba Khatun said as tears rolled down her cheeks.

Myanmar has said it was conducting counter-insurgency operations in August 2017 against Rohingya extremists who attacked police posts.

But the UN last year called for Myanmar's top generals to be prosecuted for genocide over the crisis.

Rohingya leader Mohib Ullah said the stateless minority wanted to return home, but only after they were granted citizenship, their security was ensured and they were allowed to settle back in their villages.

"We have asked the Burmese government for dialogue. But we haven't got any response from them yet," Ullah told the rally.

"We were beaten, killed and raped in Rakhine. But still that is our home. And we want to go back."

Rohingya students from schools set up by aid agencies held marches with black flags and chanted "yes Rohingya... no Bengali" -- in reference to a term Myanmar has used for the ethnic group, implying they are from Bangladesh.

The refugees burst into tears as they offered special prayers, seeking divine blessings for people who had died in the offensive. They had large banners urging Myanmar to "talk to us about citizenship and Rohingya ethnicity".

Repatriation failure

Police officer Zakir Hassan told AFP some 200,000 Rohingya took part in the peaceful gathering. Smaller rallies were also held in several other camps.

Security has been tight across Kutupalong camp, the world's largest refugee settlement and home to more than 600,000 Rohingya.

"Hundreds of police, army and border guards have been deployed to prevent any violence," local police chief Abul Monsur told AFP.

The rally came three days after the failed attempt to repatriate the refugees, which saw not a single Rohingya turn up to return across the border.

Bangladesh and UN officials interviewed nearly 300 families, but none of them agreed to go back to Myanmar where they fear they would be kept in special camps for internally displaced people.

Myanmar blamed Dhaka for the failure, saying it had not followed correct procedure when distributing so-called "verification forms" to potential returnees -- a controversial form of identification that falls short of granting Rohingya citizenship.

Bangladesh on Sunday said Myanmar's claims were baseless.

"It is Myanmar's responsibility to create a conducive environment in Rakhine through decisive actions and to reduce the trust deficit of Rohingyas," the foreign ministry said in a statement.

Bangladesh refugee commissioner Mohammad Abul Kalam told AFP authorities would continue to talk to more refugees in the next few days as part of repatriation efforts.

Amnesty International said ongoing violence in Rakhine "makes immediate repatriation dangerous and unsustainable" and called on Bangladesh to provide schooling for children in the camps, adding that it would have long-term benefits for Dhaka and the refugees.

On Saturday, Bangladesh police said they shot dead two refugees during a gunfight in a camp after the pair were accused of killing a ruling party official.