KUALA LUMPUR - World sea piracy fell 35 percent from a year ago in the first quarter of 2013, with the spotlight shifting to West Africa as navies helped keep pirates away from Somalia, an international maritime watchdog said Monday.

The International Maritime Bureau said 66 attacks were recorded worldwide in the first three months, down from 102 in the same period last year. Four vessels were hijacked with 75 crew members taken hostage and one killed during the period, according to data compiled by the London-based bureau's piracy reporting center in Malaysia.

The bureau said five attacks were reported off Somalia and in the Gulf of Aden, including one hijacking. That is down sharply from 36 cases a year ago, thanks to beefed-up naval patrols led by the US and increased security measures on ships transiting the region. In the year 2010, 49 vessels were hijacked off Somalia and more than 1,000 crew members were taken hostage.

Sea piracy plunged to its lowest level in five years in 2012. A total of 297 attacks were recorded worldwide, down sharply from 439 in 2011.

At the same time, piracy is becoming a greater concern in the Gulf of Guinea in western Africa. The bureau reported 15 attacks in the gulf, including three hijackings.

It said Nigeria accounted for 11 attacks with pirates hijacking a vessel with 15 crew members. It said a crew member of a chemical tanker was killed when the vessel was fired upon at Lagos. Another three incidents were reported in Cote d'Ivoire, with two fuel tankers hijacked, it said.

Piracy in the Gulf of Guinea has escalated from low-level armed robberies to hijackings and cargo thefts and kidnappings. Last year, London-based Lloyd's Market Association - an umbrella group of insurers - listed oil-rich Nigeria, neighboring Benin and nearby waters in the same risk category as Somalia.

The bureau praised naval forces for quick action that led to the prompt release of a hijacked Iranian fishing vessel and in another case, the capture of 12 pirates after the targeted vessel foiled an attack.

Outside of African waters, Indonesia recorded 25 incidents, but there were mainly low-level thefts.