Ottawa (CNN) Pale and grim-faced, Robert Lloyd Schellenberg sat stoically as he listened to a Chinese court sentence him to death on Monday. He had already been sentenced to more than a decade in a Chinese prison; the court's new execution order was a shocking escalation that some suspect of political motivations.

"We are all very heartbroken right now and we are all in shock. We are just overwhelmed," Gary Schellenberg, Robert's uncle, told CNN by phone from Abbotsford, British Columbia, within hours of hearing that his nephew had been given the death penalty for a drug conviction.

Schellenberg's family knows the 36-year-old former oil worker as Bob, a quiet man who has led a troubled life. Now they fear he will become the victim of a high-stakes geopolitical confrontation.

"We don't know how much to talk about right now and what to say," says Schellenberg's uncle, adding, "You're not going to find out who Bob really is." Canadian officials and his family are now scrambling to appeal the death sentence. In a statement released to CNN, his family added, "The Schellenberg family cares deeply about our Robert who is being held under very difficult circumstances in China."

Schellenberg has maintained his innocence, points out Guy Saint-Jacques, Canada's former ambassador to China, who was involved in the case from 2014 to 2016. Saint-Jacques also confirmed to CNN that Schellenberg's life in a Chinese prison is likely quite difficult. "He is likely kept in a cell with 20 to 25 people, most likely Chinese citizens, and the sanitary conditions are minimal. They are allowed to go outside about 15 minutes a day. The food is not always adequate," he says.

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