NAIROBI, Kenya - A Seychelles coast guard boat arrested three suspected pirates in the Indian Ocean off the islands that depend heavily on tourism, state media reported Sunday.

Brigitte Ahshung at the Seychelles Broadcasting Corporation said the three men were expected in port Sunday evening aboard the Andromache.

A French defence ministry spokesman said the three had previously been detained and interrogated by sailors on the French warship Nivose, which delivered 11 suspected pirates to Kenya last month.

Christophe Prazuck says the three were on a 10-metre fishing boat loaded with 13 barrels of fuel, water and food but no weapons. Pirates often use larger vessels as resupply ships that tow their small, fast speedboats hundreds of miles out to sea.

But European Union officials decided there was not sufficient proof to detain the men, freed them Friday and alerted Seychelles' officials, which picked the men up Saturday.

Pirates are now holding 17 ships and around 300 crew, including the Greek-owned cargo ship Ariana, hijacked early Saturday with a Ukrainian crew.

Special forces on a Portuguese warship seized explosives from suspected Somali pirates after thwarting an attack on an oil tanker Friday, but later freed the 19 men. Hundreds of miles away, another band of pirates hijacked a cargo ship, a NATO spokesperson said Saturday.

It was the first time NATO forces found pirates armed with raw explosives, spokesman Lt. Cmdr. Fernandes said.

The attack on the Ariana, about 1,600 kilometres from the sea corridor NATO guards and the seizure of explosives from those who attacked the crude oil tanker MV Kition may indicate the pirates are adapting their tactics as crews become better trained in counter-piracy measures.

Explosives, however, can also be used in illegal fishing.