Following his arrest Friday night, Cuban anti-communist graffiti artist Danilo Maldonado has received severe beating in prison, where he is being detained on no charges. Maldonado took to the streets of Havana Friday to celebrate the death of dictator Fidel Castro, spray-painting the phrase “he’s gone” on the outside of a building.

Maldonado, also known by his artistic name “El Sexto,” disappeared Friday night, his whereabouts unknown for days until police finally allowed his mother, Maria Victoria Machado, to see him. “Danilo was beaten, he had an asthma attack, so they beat him up,” his mother told the Spain-based Diario de Cuba. “They did not give him a inhaler… they held him down to beat him harder.” “When he asked for medical care, they beat him,” she added, calling her son “not a muscular man” and a lifetime asthma sufferer.

She added that she only found her son after his abduction through the word of mouth of a neighbor, who she says received an “intimidating” visit from police after she visited her son.

In addition to beating him, the “sadists” who abducted him stole his iPhone, his mother noted. Maldonado had used the phone to publish a Facebook video celebrating Castro’s death on Friday.

She added that police have still not charged Maldonado with a crime, and Maldonado considers himself “lucky” in spite of the arrest to have been alive to see Fidel Castro die.

Alexandra Martínez, Maldonado’s girlfriend, confirmed the story to the Miami Herald“He was badly beaten upon entering Guanabacoa and suffered a severe asthma attack.” Martínez, who lives in Miami, heard of her boyfriend’s arrest through calls from neighbors, who recalled that Maldonado was dragged away shouting “Down with Fidel! Down with Raúl!” The Herald adds that Maldonado was scheduled to return to Miami for an art event next week.

Maldonado was the first prominent member of the dissident community to be arrested following the younger Castro’s announcement that Fidel, 90, had died. His arrest was initially reported as the product of his new graffiti art, spray-painting the words se fue (“he’s gone”) on a wall in Havana. Maldonado also, however, posted a video to Facebook of him painting that wall while celebrating on the streets.

“Today is the day the mare dies,” Maldonado repeats jovially throughout the video, referring to Castro loudly as a “murderer” and “shameless,” using the female adjectives for both. He calls for an uprising against Castro.

“What we need is for people to recover their conscience and take to the streets to struggle for liberty, to earn their liberty because nobody is getting their liberty sitting at home,” he says. “How long are you going to not want to speak out?” he asks the silent people mulling about the sidewalk. “It’s been a ton of years, there will be a ton more.”

He also invites “the people of Miami to get on boats and throw a party… come over, we are waiting for you!”

In what could perhaps be the most offensive part of the video to the Cuban government, Maldonado confronts passersby and demands they say something against the communist regime. “It’s so strange out here… there are a bunch of people who don’t want to talk, with tremendous panic.”

“I see the panic in your face,” he says to a woman who scurries out of view of the camera.

Multiple human rights organizations have launched a campaign to free Maldonado. “Nobody should be arrested for expressing political views,” Americas director at Human Rights Watch José Miguel Vivanco, said in a statement. Amnesty International has launched a campaign to pressure the Cuban government into freeing him, providing contact information for Raúl Castro and his ambassador in the United States.

Maldonado’s treatment highlights concerns in Cuba’s dissident community that the repression of pro-democracy voices will grow stronger following Castro’s death. The repression, said Ladies in White leader Berta Soler earlier this week, “will continue, will worsen, will become more raw” because Castro relied on his older brother’s popularity to stay in power.