Nineteen Christians distributing leaflets during the Southeast Asian Games in Ho Chi Minh City were arrested by Vietnamese police.
A Protestant minister, Pham Ngoc Thach, remains in police custody and another minister, Nguyen Hong Quang, has staged a hunger strike in the central district of the city, the former Saigon, reported Radio Free Asia, or RFA.
A source told RFA all but four of the detainees are known to be held at local police facilities, the source said. The whereabouts of ministers Tran Mai and Le Quang Son and two assistants is unknown.
"We love this country, and we respect the law, but we are being persecuted for our beliefs," Nguyen Hong Quang said in a telephone interview, according to RFA.
Quang is asking for a meeting with local police in which he would seek the release of all 19 detainees, an end to religious oppression in Vietnam and a public apology from the authorities for the arrests, RFA said.
The ministers were arrested Tuesday, either for carrying the leaflets or handing them out, the sources said.
The publications contained game schedules and invitations to readers to consider following Jesus Christ.
Last month, the U.S. House of Representatives passed a resolution urging the government of Vietnam to "respect the right of all independent religious organizations to meet, worship, operate and practice their faith in accordance with Vietnam's own constitution and international covenants to which Vietnam is a signatory."
It also calls on the communist government "to restore freedom to all Vietnamese citizens imprisoned or under house arrest for practicing their faith or for advocating freedom of religion."
The United States Embassy in Vietnam also has been urged "to closely monitor cases of abuse of religious belief and practice, routinely visit detained clergy members, especially those in need of medical care, and report to the Congress on specific measures taken to protect and promote religious freedom in Vietnam."
The U.S. Commission on International Religious Freedom, an independent panel established by Congress to make policy recommendations to the president and secretary of state, commended the resolution, noting Vietnam "has shown, again and again, that it is determined to suppress religious freedom and maintain strict control over speech, including the media and Internet."
"There is incontrovertible evidence that the Vietnamese government has initiated crackdowns on religious leaders and believers, free speech advocates, political reformers and those championing the rights of ethnic minorities," said a statement issued by the panel.