* Benin navy says repels attackers
* Cargo, crew untouched
* Spate of attacks in Gulf of Guinea
By Samuel Elijah
COTONOU, Aug 3 (Reuters) - Pirates attacked two Panamanian-flagged ships carrying oil off the coast of Benin on Wednesday but were driven off by the Benin navy before they could steal the cargo, authorities said.
The incident was the latest in a string of attacks on ships in the Gulf of Guinea that experts say is threatening an emerging trade hub and a growing source of oil, metals and cocoa to world markets.
"The ships Golden Sifia and Aidin Panama alerted Benin's naval security forces of an armed attack," Navy Commander Maxime Ahoyo said.
"When we arrived on the scene we succeeded in chasing off 10 pirates, all Nigerians, who managed to break in but hurt no one."
He said the 54 crew aboard the two ships, who were in the process of transferring oil ship-to-ship, were able to hide after the pirates boarded and fired their weapons.
Some 26 pirate attacks have been recorded off Benin -- which neighbours oil-rich Nigeria -- since the start of the year, including an attack on an Italian diesel tanker last week.
Piracy in the Gulf of Guinea is rising but is not on the scale seen off Somalia, where armed seaborne gangs are making millions of dollars in ransoms and becoming increasingly violent. (Writing by Richard Valdmanis)