Bahraini security forces beat the detained poet Ayat al-Gormezi across the face with electric cable and forced her to clean with her bare hands lavatories just used by police, members of her family said yesterday in a graphic account of the torture and humiliation suffered by those rounded up in the Gulf nation's crackdown on dissent.

The 20-year-old trainee teacher, who spent nine days in a tiny cell with the air conditioning turned to freezing, is due back in court this weekend on charges of inciting hatred, insulting the king and illegal assembly, and her family fear she may suffer further mistreatment in custody amid threats of another round of interrogation.

Masked police arrested Ayat at her home on 30 March for reciting a poem criticising the monarchy during a pro-democracy rally in the capital Manama in February. Her family were able to talk to her by phone from prison, but they only learned about her mistreatment, amounting to torture, when she spoke to them at her arraignment earlier this month.

In a phone interview with The Independent from Bahrain yesterday, her mother, Sa'ada Hassan Ahmed, related Ayat's account of what happened after her arrest. The details of her interrogation and imprisonment are similar to the experiences of other women detained by Bahraini security forces since they launched a full scale repression on 15 March against all those demanding democratic reform in the island kingdom.

Ayat gave herself up to police after they threatened to kill her brothers. She was taken away in a car with two security officials – a man and a woman – both of whom were masked and dressed in civilian clothes. They immediately started to beat her and threaten her, saying she would be raped and sexually assaulted with degrading photographs of her put on the internet.

"When she reached the interrogation centre in Manama she was put in the very small cell and kept there for nine days," her mother said. "The beatings with electric cable made her lips swell up." At times, Ayat thought the air conditioning in the cell was emitting some form of gas, which made her feel she was suffocating. Throughout this period the police made no real attempt to interrogate her.

Her family say the days after Ayat was taken away was a period of intense psychological torture. "We knew nothing about what had happened to her though we heard rumours that she had been raped or killed," her brother Yousif Mohammed said.

Her mother went from police station to police station asking for news of Ayat, but learned nothing. Sa'ada was finally told by the police that she should file a missing persons report, though she complained that this was absurd since it was the police who had detained her daughter.

And in a sinister development, pictures of Ayat began to turn up on dating and pornographic websites. This may relate to the threats made by police when she was first arrested that shameful photographs of her would be posted online.

After nine days, Ayat was moved to Isa prison and, 15 days after she was first taken away, she was allowed to make a phone call to her parents telling them that she was alive. The physical torture stopped, but she was kept under psychological pressure.

"At some point," her mother says, "she was forced to sign a document but she was blindfolded and did not know what it said."

She was told to clean up other cells and the corridor of the bloc she was in but was allowed no contact with other prisoners. On several occasions she was taken back to the interrogation centre where she had first been held and a video was taken of her giving her name and saying that she was a Shia and she hated Sunnis.

The majority of the Arab population in Bahrain are Shia and the ruling Al-Khalifa royal family are Sunni. The government have been trying to portray demands for democratic reform as an anti-Sunni conspiracy orchestrated by Iran.

Asked for further details of Ayat's interrogation in Isa prison, her mother said she did not know because they did not have long enough to talk when they met during the arraignment. They were told the previous day to bring a lawyer, though it is unclear how freely he was able to talk to his client.