Burundi has accused Rwanda of holding Burundian refugees hostage and militarily training them to oust Pierre Nkurunziza's government.
The allegations came after more than 2,000 Burundian refugees were repatriated from Rwanda last week, with Kigali saying they refused to comply with the national laws.
Last month, 33 Burundian refugees were arrested by the Rwandan authorities allegedly for inciting fellow refugees to reject assistance from United Nations High Commissioner for Refugees (UNHCR).
Rwanda Foreign Affairs Ministry said a number of refugees refused to provide biometric data or comply with public health requirements and that after consultations with the UNHCR and the asylum seekers, the group preferred to be repatriated to their motherland.
The government of Rwanda said that it was ready to provide asylum to those who comply with national laws as well as the international convention on refugees.
But Burundi government spokesman Philippe Nzobonariba claimed that Rwanda does not only host the 2015 coup plotters, is also recruiting young children to join armed group.
"This constitutes a serious violation of the treaty and international conventions, which Rwanda ratified that prohibit arming and militarily train refugees," said Mr Nzobonariba.
Mr Nzobonariba also accused Rwanda of trying to disrupt the referendum that is expected to be conducted next month.
The refugees who were repatriated from Rwanda are believed to be followers of a Prophet Zebiya Ngendakumana, who say their faith prohibits them to use biometric registration.
"They wanted to separate us and we could not accept any separation because we always pray together and that's why we refused and decided to return to Burundi," said Baranjoreje Barthelemy, one of the refugees who were repatriated from Rwanda.
In September last year, at least 36 Burundian refugees, followers of Zebiya, were reportedly killed by Congolese forces during a protest in South Kivu of Kamanyola.
Early last month, the same group of Burundian refugees fled DRC to seek asylum in Rwanda but within less than a month they requested to be repatriated to Burundi.
"The refugees were received by the police at the border and identified by the police and police will continue to protect them while adopting in their new life, however, many of them testified that young people were detained with the objective to recruit and train them," Burundi police spokesman Pierre Nkurikiye told The EastAfrican.
Burundi and Rwanda relation has continued to deteriorate since 2015 when President Nkurunziza vied for another term in office, Rwanda accused Burundi of hosting the Democratic Forces for the Liberation of Rwanda (FDLR) rebels, who are said to have committed the 1994 genocide.
Burundi also accuses Rwanda of sheltering May 2015 coup plotters and militarily training refugees in efforts to oust the current government.
Contacted, Rwanda's State Minister for Foreign Affairs, in charge of the East African Community (EAC), Olivier Nduhungirehe said that the claims of military training were not worth commenting on.
Rwanda said all the refugees, as they arrived from DR Congo, were sent back to Burundi. There were slightly over 2,500 and were sent back to their country after they rejected biometric verification, citing religious belief.
Rwanda's Ministry of Disaster Management and Refugees said the verification like vaccination is among the basic conditions they had to fulfill to be granted refugee status in the country.