GAZA, March 11 (Reuters) - A British journalist arrested by Hamas in the Gaza Strip last month and held for nearly four weeks on suspicion of spying for Israel, was being released on Thursday, his lawyer and Palestinian officials said.

Paul Martin was detained on Feb. 14 while on a visit to Hamas-run Gaza to give evidence in a court case involving a local man accused of working with the Israeli security services.

Martin's lawyer, Sharhabeel al-Zaeem, told Reuters he expected the journalist to be freed without penalty shortly and to be handed over to British and South African consular officials. They would escort him out of Gaza into Israel later in the day, he added.

Paul Martin will be expelled today, a senior Palestinian source in the Hamas-run government of Gaza told Reuters.

London-based Martin, who is in his 50s, has reported frequently from Gaza, providing freelance reports for television and newspapers. British officials have said throughout his detention that they were providing consular support. They have made little other public comment on the case.

Human rights groups have criticised both Hamas Islamists and Palestinian President Mahmoud Abbas's Palestinian Authority, which rules in the Israeli-occupied West Bank, for detaining journalists and placing other curbs on media freedoms. (Reporting by Nidal al-Mughrabi, editing by Alastair Macdonald)