YAOUNDE, July 8 (Reuters) - Gunmen kidnapped five Chinese fishermen off Cameroon's Bakassi peninsula earlier this week, a security source said on Wednesday, and local rebels blamed militants from Nigeria's Niger Delta for the raid.

Nigeria's most prominent militant group denied involvement in the kidnapping, the latest in a series indicating that insecurity is spreading from the Delta, where attacks on oil installations and workers have slashed oil output since 2006.

"We have just received information that some Chinese fishermen were kidnapped in Bakassi," a security source in the Cameroonian port city of Douala told Reuters.

The source said the incident took place on Monday but gave no further details. There was no immediate confirmation from the Cameroonian or Nigerian authorities of the incident.

Ebi Dari, the commander of the Bakassi Freedom Fighters (BFF), a group opposed to last year's return of Bakassi from Nigeria to Cameroon, said gunmen from the Nigerian oil town of Port Harcourt were responsible for the kidnapping.

"(The militants) told us they were actually pursuing a boat carrying some workers of a Western oil company which ran out of sight. So, frustrated, they seized the five Chinese men aboard the fishing vessel as they returned to their base," Dari said.

"The fishermen were just victims of circumstances, they just found themselves in the wrong place at the wrong time."

Dari said that the gunmen wanted a ransom payment.

The Movement for the Emancipation of the Niger Delta (MEND), which has sabotaged pipelines and bombed oil facilities since Nigeria's military launched an offensive against it earlier this year, denied invovled in the kidnapping of the Chinese.

Cameroon and neighbouring Equatorial Guinea, which is Sub-Saharan Africa's third largest oil producer, have both come under attack in Delta-style raids over the last few years.

The oil- and gas-producing nations in the Gulf of Guinea are seeking to improve security collaboration and are receiving support from Western governments, which are keen to protect strategic interests in the region. (Reporting by Tansa Musa; Writing by David Lewis; Editing by Giles Elgood)

AlertNet news is provided by