WASHINGTON — The Guatemalan journalist Jose Ruben Zamora could be returned to prison after an appeals court Friday overturned an order that had moved him into house arrest. Zamora, who is the founder of the newspaper El Periodico, had been detained on questionable grounds for two years before being granted house arrest in October. But prosecutors appealed the order, and Friday the appeals court ruled that Zamora, who is 68, should return to prison. The journalist’s son confirmed the appeals court decision and said his father’s lawyers had been notified, according to The Associated Press. Zamora was arrested in July