Le Van Hai held for two months after complaining his home was confiscated for wastewater treatment plant.
Harassment follows lawyers' complaints of court 'irregularities' and defendants' testimony alleging torture by police.
Vietnam's prime minister and Indonesia's foreign minister warn ASEAN member states that rising tensions in the South China Sea threaten regional stability and peace.
Nineteen out of 29 villagers on trial say they were tortured by police during questioning after their arrest in January.
A bomb attack in Ho Chi Minh City and a failed plot in Bien Hoa are tied to a Vietnamese exile group based in Canada.
Defense attorneys say they are not allowed to meet with their clients, and object to prejudicial videos shown in court.
Defendants in the trial set for Sept. 7 have been denied access to lawyers and family, signers of the letter to the UN Human Rights Council say, urging the UN to speak out about the case.
Vietnam has a documented history of tension with neighboring China over oil exploration in the South China Sea.
Red tape stymies attempt by Trinh’s father to meet his second detained son.
Police in Hanoi tell concerned father to petition police in Hoa Binh province, which turned him away two days earlier.
Hunger strikes are often the last resort for political offenders in Vietnam being pressured to confess their 'guilt,' one former prisoner says.
Authorities say one detainee, Trinh Ba Tu, in the 20th day of a hunger strike.
The arrests come two days after the Malaysian coast guard shot and killed a Vietnamese fisherman whose boat allegedly attacked the Malaysian ship.
A Vietnamese sailor is shot and killed when his boat allegedly attacks a Malaysian ship sent to inspect it in Malaysian waters.
Truong Duy Nhat spoke during the hearing and disclosed that he was spirited from Thailand to Vietnam through Laos.
Meanwhile, another blogger is indicted for publishing information on the deadly Dong Tam land dispute.
Seventeen have now died, with all fatalities linked to the recent outbreak in the coastal city of Danang.
Targets of the protest say the 'spontaneous' groups were incited by authorities, however.
Truong Duy Nhat, who is serving a 10-year prison term for 'abusing his authority' in a land-fraud case, has called his arrest politically motivated.
Cases have surged by 227 since July 25 Danang outbreak.