Australian professor and his son freed after being allegedly tortured in Qatar

An Australian public health professor allegedly tortured and held in secret in a Qatari jail cell has been freed after five months detention, the Guardian can reveal.

Biostatistician Prof Lukman Thalib, 58, and his son Ismail Talib, 24, were arrested at their home in Doha on 27 July and held at undisclosed locations.

No charge or explanation for their detention was offered, though the arrests came three months before the United States named another of Prof Thalib’s sons, Victorian resident Ahmed Luqman Talib, as an alleged “financial facilitator” of al-Qaida.

Prof Thalib and Ismail Talib have alleged they were tortured while in Qatari detention. They say they were placed in stress positions for prolonged periods, suffered sleep deprivation, isolation and sensory bombardment, including the use of harsh lights 24 hours a day.

Related: Australian professor and son detained in Qatar for five months without charge

Prof Thalib was, at the time of his arrest, the acting head of Qatar University’s public health department and was helping the country with its Covid-19 response. He had previously lived in Brisbane and had worked with Griffith University.

His daughter, Maryam Luqman Talib, said the family was “overwhelmed with joy” at their release.

Maryam Talib and other relatives say they were not notified of the arrests for 40 days.

“My father and brother are naturally relieved to be back with their family but are still struggling to comprehend and come to terms with the chilling and horrifying five months that they left behind them,” she told the Guardian.

“The extent of damage done on their health is yet to be ascertained but what can be seen to the naked eye speaks volumes of the merciless torture they went through.”

The family was assisted by CAGE, a London-based organisation, which believes the arrest and treatment of the pair was a form of “collective punishment” for the uncharged allegations against Ahmed Luqman Talib.

Ahmed Luqman Talib was named by the US state department in mid-October as a facilitator of al-Qaida and accused of using his gem-trading business to move money across the globe. A short time later, Victorian police, the Australian Security Intelligence Organisation and the Australian federal police raided his home.

No charges have flowed from the raid.

Prof Thalib and Ismail Talib were held for roughly five months in Qatar.

Maryam Talib said that, even prior to their release, Qatari authorities could offer no justification for their detention.

“There was also no official explanation provided that indicated that the detention was linked to my brother Ahmed’s uncharged allegations,” she said. “As we have previously stated, they were detained three months prior to the surfacing of these allegations so we are yet to understand what has motivated this arbitrary detention.”

She said the pair had confirmed they were questioned under “very harsh conditions, often taken for interrogation while in a state of extreme disorientation and mental confusion”.

They were visited by consular officials with the Department of Foreign Affairs and Trade in recent months. Dfat confirmed it had provided consular assistance to the pair, but otherwise declined to comment.

Both Prof Thalib and Ismail Talib have now fled to Turkey but plan to return to Australia when they recover.

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Maryam Talib said there were many “unanswered questions” about the role of the Australian government in the matter.

“Neither Dfat nor the Australian embassy in Qatar have any clear role in securing their release, despite our repeated requests to intervene and use all diplomatic channels to put pressure on the Qataris,” she said.

CAGE head of casework Naila Ahmed said she believed the media pressure brought to bear on the Qatari government had led to the release. Ahmed said there were still unresolved questions about how much the Australian authorities knew of the alleged torture and secret detention of the Thalibs.

“It is crucial that the Australian authorities explain in full the level of their involvement and explain their perplexing lack of support to the Thalib family throughout this ordeal,” she said.

The Qatar government was approached for comment.