Marginalised and misunderstood, Chinese Vietnam veterans -- who fought in a little-celebrated war against their southern neighbours -- risk beatings and prison in a new battle with government officials.
Teng Xingqiu is one of thousands of retired Chinese soldiers staging an increasing number of protests over unpaid benefits and unnerving Communist authorities.
"The police told me they hoped I'd die in jail," said Teng, whose activism resulted in him being sentenced to three years in prison in 2009.
A thin man whose body bears scars he says result from police violence, the 56-year-old scanned the streets for surveillance cameras before choosing a run-down restaurant as a safe meeting spot.
The current tensions over Beijing's deployment of an oil rig to disputed waters are only the latest strain between the Communist neighbours.
Teng was posted to the border area during a brief but bloody war in January 1979 -- China's last major land conflict -- launched by Beijing to punish Hanoi for invading Cambodia and overthrowing the genocidal Pol Pot, a Chinese ally.
"As Chinese citizens, of course we wanted to go to the front. A lot of my army friends were killed. Many members of my platoon were shot dead," he said.
China reportedly acknowledges it lost 6,954 soldiers. Other estimates place its toll at more than 20,000, with even higher figures for Vietnamese casualties.
No national memorial to the conflict exists, and Beijing rarely mentions it, even when denouncing Hanoi.
The war was "deadly and atrocious on the ground," according to US historian Xiaoming Zhang.
"Ordinary Vietnamese worked in secret with the army, old men and women would even shoot at us, it was really terrifying," Teng said.
Beijing declared victory and withdrew its troops less than a month after they reached an outpost near Hanoi.
Vietnam also regards it as a success, saying it repelled Chinese forces.
- Threat to social stability -
The US has produced hundreds of films and novels about its own Vietnam war, but China's experience there is rarely spoken about, and first-hand accounts are heavily censored.
Around the same time, China began the landmark reform drive that partially replaced its state-planned economy with free markets.
Leaving the army, Teng was assigned a job in a state-run firm, but was later laid off and could only find work as a rubbish collector.
Soldiers of the time were "left behind" by change, said Neil Diamant, a professor at Dickinson College in the US who has studied veteran activism, and now many are "living hand to mouth with mounting medical expenses".
China often vows aid for its veterans -- estimated to number millions -- but rules conflict and are poorly enforced.
Teng says he makes about 1,000 yuan ($160) a month from odd jobs but thinks the government should find him a wage matching the approximately 2,800 yuan average income in his home town of Yiyang, in the central province of Hunan.
He was sentenced to more than three years in jail for "assembling to disturb order in a public place", after banding together with other former soldiers who donned army uniforms to protest outside government offices.
China sees hundreds of demonstrations involving thousands of veterans every year, according to rights groups, with more than 10,000 reportedly doing so in 11 provinces late last month.
Such demonstrations are one of the biggest threats to social stability in the country, Xue Gangling, dean of the China University of Politics and Law, told Chinese media outlet Caixin last year.
China's President Xi Jinping has in the last year vowed to cut army personnel as part of sweeping military reforms aimed at creating an army oriented towards sea and air combat -- raising the possibility of further veteran unrest.
But authorities view any organised dissent as a risk, and crack down harshly.
Significantly, any suggestion of disloyalty in the military -- a pillar of Communist control -- is anathema to China's rulers, who constantly stress the need for the People's Liberation Army to follow Party orders.
Censors block news of military-linked protests, Chinese reporters told AFP.
"Army topics are sensitive and people sense danger so it's particularly hard for veterans to mobilise outside support," said Diamant. "Orphans can do it, environmentalists can do it, but not veterans."
- 'We'll beat you to death' -
Teng has repeatedly tried appealing to central authorities in Beijing, but local officials detained him in illegal "black jails", a common fate for protesters.
He suffered daily beatings during his prison term, he says, and guards forced him to eat food scraps off his cell floor.
"They said, if you don't admit guilt, we'll beat you to death," he told AFP.
Now his communications are monitored and police -- who installed a surveillance camera outside his home -- detained him for 24 hours after he was contacted by AFP, warning him not to speak to the media.
Yiyang officials refused to comment on Teng's case when contacted by AFP.
Wang Guolong, a fellow protester who spent 14 years in the army, said: "They arrested Teng as a warning to stop us uniting, but our situation is the same... There are millions of veterans like us across the country."
The ex-soldiers infuse their rhetoric with nationalism, with one group in neighbouring Hubei province singing a "battle hymn" pledging to "smash US imperialism" at a recent protest.
Teng is still a staunch supporter of Beijing's assertive foreign policy, and uses the name "South Sea Warrior" online.
"Defending your rights is more dangerous than fighting a war," he said. "You can be arrested at any time."