ISIS leader Abu Bakr al-Baghdadi has called on jihadists to free detainees held in jails and camps in what is believed to be his first public statement since April.

In a 30-minute audio recording released late on Monday, the Islamist questioned how a Muslim can enjoy life when Muslim women are held in “prisons of humiliation run by crusaders and their Shia followers.”

While urging those held in camps to be patient, he called on Isis militants to do all they can to spring the jihadists. He also called for interrogators and judges that are quizzing Isis fighters to be targeted.

Isis was defeated in Iraq in 2017, being driven out of its self-declared caliphate before losing ground in Syria in March this year.

The jihadist group has dwindled to a rump and reconfigured into a network of sleeper cells. These carry out guerilla attacks against Kurdish forces in the democratic enclave in northern Syria known as Rojava.

Kurdish forces have faced attack from Turkey, which allied with jihadists from the Free Syrian Army to launch Operation Olive Branch last year.

The illegal invasion of the peaceful region of Afrin was backed by most Western countries, supporting Turkey’s right to “protect its borders” from a supposed terrorist threat.

But Ankara has been supporting jihadist groups in Syria with Turkish intelligence services facilitating their crossing into the country from Turkey.

Baghdadi is the world’s most wanted man with a $25 million (£20.1m) bounty on his head for leading a reign of jihadist terror across the globe. In Monday’s audio recording he claimed Isis was carrying out attacks in a number of different countries.

Many of its fighters have been taken prisoner by the largely Kurdish Syrian Democratic Forces. Around 73,000 are being held in the al-Hawl camp in north-eastern Syria’s Hasakah province.

Women detained at the camp have raised thousands of pounds from sympathisers through the Justice for Sisters campaign organised through a German intermediary.

Another campaign aimed to raise funds to pay smugglers to free them from the camp where conditions are said to be deteriorating.

Turkey’s authoritarian President Recep Tayyip Erdogan has threatened to send back 3.6 million Syrian refugees to the so-called safety buffer zone in the north of the country.

Kurds have warned of an “ethnic cleansing” programme by the Turkish state and the possible re-emergence of Isis in the region.