John Malumba Wasswa says it suddenly feels very lonely without his twin brother around.

Yesterday just after lunchtime, an unknown assailant arrived at the house of his brother, David Kato (in Uganda people are often given their own local name). Not long afterward, a visiting neighbor found Kato lying on his floor, with a severe wound to his head. He died on the way to the hospital.

Kato's murder is more than just a family tragedy, Mr. Wasswa concedes. One of only a handful of campaigners, Kato was a prominent gay rights activist in Uganda – a tough job in a country where homosexuality is illegal and gay men and women regularly face harassment.

“When my brother wanted to do something then no one could stop him,” Wasswa says. “He was very brave.”

And in recent months, Kato had needed all of his courage and determination.

Late last year, the Rolling Stone, a local tabloid, splashed Kato’s picture across its front page, along with photographs, names and addresses of a handful of other men it called Uganda’s “top homos.” The accompanying editorial ran under the headline “Hang them.”

Earlier this month, Kato and two fellow activists successfully sued the Rolling Stone and got a judge to impose an injunction barring all media in Uganda from revealing the identities of alleged homosexuals. It was a rare victory in a country where gay rights activists said the atmosphere was becoming increasingly poisonous.

“Kato was much more conscious of his security these days,” says Kato’s lawyer, John Francis Onyango. “He was conscious that something could happen.”

Onyango said that it was too soon however to know if Kato’s murder was down to a homophobic attack, but said that Kato had been subjected to verbal and physical threats recently.

The current antigay crusade in Uganda hit the headlines in 2009 when a bill tabled in the Ugandan parliament proposed imposing the death penalty for some homosexual acts. The proposed legislation sparked a storm of international controversy – described as “odious” by President Obama – and was quietly put on a backburner. It remains before parliament, however.

Much of the current impetus for the antigay campaign began with the arrival of evangelical church groups- some from the US – which began to get increasingly involved about two years back, says Michelle Kagari, Amnesty International’s Deputy Director for Africa.

“Things started going to a whole new level when the churches got involved,” Ms. Kagari says.

But while it is the current antigay campaign in Uganda that has garnered international attention, homophobia remains rife across Africa. Homosexuality is illegal in 37 countries on the continent.

And from attacks in Senegal, Nigeria, Gambia, and Cameroon to the imprisonment of a same-sex couple in Malawi and the "correctional rape" of lesbians in South Africa, more cases of abuse are being reported, Kagari says.

Whether this is because of a general rise in homophobia on the continent is debatable, however, she argues.

Instead, she says, it could be a result of the rapidly increasing number of local activists and the fact that like David Kato, ever more gay Africans are taking a stand for their rights.