Tunis - The leader of a protest movement in northern Morocco was "severely" beaten and verbally abused by police during his arrest, Human Rights Watch and Amnesty International said on Thursday.
Nasser Zefzafi - leader of Al-Hirak al-Shaabi, or the "Popular Movement" - was detained on May 29 in a village 50km from the city of Al-Hoceima along with two fellow activists.
A dozen police officers broke down the door of his house in the early hours of the morning, he told his lawyer at a Casablanca prison, according to a joint statement by the rights groups.
"The police broke furniture and windows, and assaulted the three men even though they offered no resistance," it said.
"He said he had a 1.5-centimetre cut on his scalp, another one below his left eye, and bruises on his back."
The rights groups said the police had insulted the three men in vulgar terms, pressing them to shout "Long live the king!" and calling them "separatists".
The police then transported the men to the northern city of Al-Hoceima before flying them, hooded and handcuffed, to Casablanca, they said.
"There, the police took Zefzafi for medical care, including stitches to his scalp, and gave him clean clothes to replace his blood-stained ones," the statement read.
Al-Hoceima has been rocked by worsening social unrest since the gruesome October death of a fishmonger crushed in a rubbish truck as he tried to retrieve swordfish that had been thrown away by the authorities because it had been caught out of season.
Demands for justice and anger over the region's perceived marginalisation snowballed into the wider grassroots movement.
More than 100 people have been detained in Al-Hoceima since the end of May in a wave of arrests targeting the core of the movement.
Last week a court sentenced 25 demonstrators and suspected Hirak members to 18 months in jail each, according to their defence lawyer.
Zefzafi was arrested on charges of "attacking internal security".
"Moroccan authorities should investigate the credible allegations of police violence against Zefzafi," and refrain from filing charges over "peaceful speech or protest", said Sarah Leah Whitson, HRW's Middle East and North Africa director.
Five detained activists including Zefzafi have threatened a three-day hunger strike over the conditions of their detention, their lawyers said.