Four Chilean men have been convicted of first-degree murder for beating to death a gay man and carving swastikas into his body.

Daniel Zamudio's death set off a national debate in the country about hate crimes that led its congress to pass an anti-discrimination law.

As the judge read the guilty verdict, Zamudio's mother sobbed. Her son's killers stood motionless and stared blankly at the floor.

Judge Juan Carlos Urrutia said Patricio Ahumada Garay, Alejandro Angulo Tapia, Raul Lopez Fuentes and Fabian Mora Mora were guilty of a crime of "extreme cruelty" and "total disrespect for human life".

The judge said the attackers burned Zamudio with cigarettes, beat him with glass bottles and broke his right leg with a heavy stone before they abandoned him in a park in Santiago on 3 March 2012.

The sentence will be read on 28 October. Prosecutors are asking for jail terms ranging from eight years to life in prison.

"We're satisfied with this ruling. There's a before and an after the Zamudio case," said Rolando Jiménez, president of the Gay Liberation and Integration Movement.

"It generated such outrage because of the brutality, the hate, that it helped raised awareness," he said. "We've witnessed a cultural change that finally led to an anti-discrimination law."

The law had been stuck in congress for seven years, but President Sebastián Pinera put it on the fast track after Zamudio's murder. The law adopted last year enables people to file anti-discrimination lawsuits and adds hate-crime sentences for violent crimes.

Zamudio, a clothing store salesman, was the second of four brothers. He had hoped to study theatre.

"Nothing can change the tremendous pain suffered by Daniel's parents," presidential spokeswoman Cecilia Pérez said. "But there's no doubt that today some tranquility has finally reached their hearts. It's the tranquility that comes with justice."