HANOI: The United States and the European Union have called on the Vietnamese government to release a popular blogger arrested earlier this week for alleged anti-state writing.

Nguyen Ngoc Nhu Quynh, who blogs as Me Nam, was arrested Monday in the south central province of Khanh Hoa for what authorities say were her Facebook and blog posts that distorted truth and instigated the public to oppose the communist government.

The ambassadors from the United States and European Union to Vietnam said in separate statements that the arrest goes against Vietnam's international obligations and domestic laws on human rights and called for her release.

US Ambassador Ted Osius said in a statement Wednesday that he was "deeply concerned" by recent actions taken by the government against peaceful human rights advocates, including the arrest of Quynh and the jailing of several other bloggers and activists.

"This trend threatens to overshadow Vietnam's progress on human rights," he said, adding the United States was urging the Vietnamese government to ensure its laws and actions are consistent with its international obligations and its Constitution.

The head of the European Union Delegation to Vietnam, Bruno Angelet, said in a statement that it was "important to ensure the safety of human rights defenders and protect their rights to express their opinions peacefully, freely, without threats or impediments, in line with Vietnam's international obligations."