UPDATE 1-Nigeria militants free UK hostage after 9 months

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ABUJA, June 12 (Reuters) - A Nigerian militant group said on Friday it freed a British oil worker held captive for nine months in the creeks of the Niger Delta.

The Movement for the Emancipation of the Niger Delta (MEND) said Matthew Maguire was released to authorities in Nigeria's oil hub Port Harcourt in Rivers state.

"MEND can confirm that Matthew Maguire was handed over to the Nigerian government officials at a secret rendezvous," the militant group said in a statement.

Two sources -- a private security official and a second person close to the negotiations -- confirmed to Reuters the Briton's release.

Maguire was among more than 20 people taken when their oil supply vessel was hijacked on Sept. 9 in the Niger Delta, home to Africa's biggest oil and gas industry. All except Maguire were freed months ago.

The Briton was believed to have been held hostage by MEND for the longest period of time since the group launched its campaign of violence against the oil sector three years ago. (Reporting by Randy Fabi; Editing by Angus MacSwan)