Concern was mounting today for the well-being of a Bradford charity worker under arrest at a high-security military jail in Israel.

Humanitarian aid worker Ayaz Ali, 36, was first being held under Israeli law but this has now been changed to detention under military law in the occupied territories, considerably reducing his rights.

He was detained for a further ten days at a court hearing on Friday. Israeli authorities have cited security reasons' for his detention but have offered no further explanation to British officials and he has still not been charged.

Mr Ali has been held at Ashkelon prison since his arrest at a checkpoint near Ramallah in the West Bank on Tuesday, May 9.

A spokesman at Birmingham-based charity Islamic Relief, for which Mr Ali works as a programme manager, said: "Ayaz is in a high-security military prison.

"He has no exercise facilities and very few reading materials. He's in a small, cramped cell that he is sharing with another inmate."

Mr Ali, who grew up in Shipley, was arrested while travelling in a taxi to meet colleagues at British-based charity Islamic Relief's West Bank office. He had been working in Israel delivering aid to Palestinians since December.

The Islamic Relief spokesman said: "We are requesting an appeal against the ten-day extended detention and are hoping to get another court date in the next few days to try to overturn the decision.

"Officials at the British Consulate in Jerusalem and the Embassy in Tel Aviv have met Ayaz twice now and are continuing to push for his conditions to be improved."

Mr Ali's family, who still live in Shipley, are said to be deeply distressed by his detention. His wife is due to give birth next month.

"The situation is causing great distress to Ayaz's family," said the Islamic Relief spokesman. "We are all very concerned for him and have been working tirelessly to try to secure his release."

A Foreign Office spokesman said: "We are continuing to press the Israeli authorities to either lay charges against him or release him."

The charity said Mr Ali's arrest was causing a great deal of disruption to its work.

The spokesman said: "Ayaz has been held for two weeks now and our work in Gaza and elsewhere is beginning to suffer as a result."

e-mail: jennifer.sugden@bradford.newsquest.co.uk