GAZA, March 1 (Reuters) - A Palestinian court on Monday extended by 15 days the detention of a British journalist arrested by Hamas police in the Gaza Strip last month on suspicion of collaborating with Israel's security services.

Paul Martin, a freelance journalist, was taken into custody on Feb 14. His lawyer, Sharabeen al-Zaeem, said prosecutors told the court more time was needed to investigate the charges.

Hamas officials said Martin was held for his connection with a Palestinian prisoner accused of collaboration with Israel's undercover security services.

A spokeswoman at the British Consulate General in Jerusalem that oversees affairs with Palestinians in the West Bank and the Hamas-run Gaza Strip declined to comment on the remand order.

Human rights groups have criticised both Hamas Islamists and Palestinian President Mahmoud Abbas's Palestinian Authority for detaining journalists and placing other curbs on media freedoms. (Reporting by Nidal al-Mughrabi, Writing by Ori Lewis; Editing by Janet Lawrence)