According to the department, one of the men living in Dong Nai Province and the other in Lam Dong Province. One of them, Nguyen Xuan Long, is the admin of the Vit Bau Facebook page.
Long allegedly admitted that the fan page was set up in 2015 by an American-Vietnamese woman in the US and he was invited to become its admin this September. He said they published 10 posts a day and many of the stories were fake.
The Ministry of Public Security is expanding the investigation.
Since late October, rumors started circulating online that the State Bank of Vietnam was going to revalue the Vietnam dong, a story that encouraged people to buy gold or foreign currency. Supposed images of the new Vietnam dong currency were circulated with a claim that the printing process had begun.
The page was also accused of spreading and inciting anti-government posts.
On December 1, the State Bank of Vietnam denied the rumors and said they were deliberately being circulated to cause damage. On December 6, Prime Minister Nguyen Xuan Phuc ordered the police to find the source of the rumors, saying that it had badly affected the the economy and the public should strongly criticize such behavior.
original source: http://english.vietnamnet.vn/fms/society/169667/two-arrested-for-spreading-rumour-of-banknote-change.html