The Stony Brook professor finally got word back to his university. He wanted to tell his students that unfortunately their recommendation letters would be delayed. He had been jailed in his native Cameroon — partially because of a Facebook post.

Patrice Nganang is no stranger to long distances and straddling different worlds: He was born in the Central African nation and now teaches literature on Long Island. His internationally acclaimed and award-winning novels explore decades of Cameroonian history and politics. In the United States, he campaigned as a volunteer for President Barack Obama’s election.

He makes a punishing, multi-hour commute to Stony Brook from New Jersey, where he lives — a breeze compared to his frequent flights back to Cameroon to stay connected. But his most recent visit didn’t have a routine ending. Since last week, family and friends say he has been held at a detention center in the capital after posting a charged Facebook comment about the Cameroonian president. Supporters have been rallying to get him back to his family, and his students in New York.

Think our country has political divisions?

Nganang’s friends describe him as an intellectually intense man who believes in the power of literature, education and civic engagement to create change. It’s clear that he thinks change is necessary in his native country, where octogenarian Paul Biya has been president for nearly four decades. A collection of his political essays is titled “Contre Biya” in French, or “Against Biya.”

We think our country has problems and political divisions? In Cameroon, Boko Haram terrorists threaten civilians in the north. English-speaking areas in the west of the country are simmering over discrimination by a French-speaking majority that, for example, don’t translate some laws. It’s one of multiple divides that are an inheritance of the country’s colonial past. Under Biya, security forces have violently opposed a secessionist movement in anglophone areas. In October, Amnesty International said at least 17 people were killed in clashes.

Nganang traveled to the west to see for himself in recent weeks. Friends and family say the dire situation he witnessed prompted an emotional Facebook post — including declarative language in French about putting a “bullet” into Biya’s “forehead.”

A lawyer for the writer has said Nganang doesn’t own weapons or work with armed groups. In an email, his wife, Nyasha Bakare, said he was “overwrought” when writing the post: “I’ve known him for 23 years now and he is a completely nonviolent person.”

Yet Nganang remains imprisoned with no formal charges filed, according to a source with knowledge of State Department conversations. The government is investigating social media language and also a lack of a valid visa to visit Cameroon, the source said on Wednesday. (Nganang now has U.S. citizenship, and Cameroon does not consider Cameroonian passports to be valid if the individual takes citizenship elsewhere.)

Supporters say Nganang could be charged with having issued a death threat.

Threats against American presidents are also taken seriously. But robust protections for freedom of speech, even angry speech, tend to be honored in the United States when offenders don’t show intent to harm: from singer Ted Nugent telling President Barack Obama to “suck on my machine gun” to comedian Kathy Griffin taking a picture showing a decapitated, bloody President Donald Trump.

Nganang has devoted a career to peaceful organizing here and in Africa, building infrastructure like schools and footbridges — sometimes with his own hands — through the organization Generation Change. He has given talks about activism, and supported the campaign to get another Cameroonian writer released from prison.

“Writers are working with words, they’re not working with physical bullets,” says his American translator, Amy Reid.

She says his writing celebrates engagement but decries violence, such as the novel “Dog Days,” which ends with a women-led street protest after a police chief shoots a child.

Testing limits, an uncertain future

New technologies, however, appear to have made Nganang’s bind more complicated.

After his visit to the chaotic western part of the country, Nganang also published an essay on the website Jeune Afrique, which argues for “change at the top of the state” to resolve the conflict. That would seem unlikely to merit law enforcement attention in free societies. His supporters argue that the Facebook language is a more emotional, less moderated version of the political argument.

There as here, Facebook seems to be at the center of politics, with people testing limits and adjusting to so much writing being shared so widely.

In a restive country where the UN secretary-general condemned violence in October, Nganang’s supporters worry that ill-conceived social media activity could result in far more than angry comments or even a visit from police.

The State Department has said it’s aware of the arrest of a U.S. citizen in Cameroon, and “takes its obligation to assist U.S. citizens abroad seriously.”

Other supporters in American universities and organizations like PEN America and the Committee to Protect Journalists have rallied to Nganang as he navigates an uncertain future. But one thing is certain: With a book on the way from a New York-based publishing house and paragraphs being composed in prison, according to a friend, his words will continue reverberating.