The gunmen were held by the frigate HNLMSDe Ruyter in two skiffs 200 miles from the coast.
The Dutch warship sent a helicopter to theposition after a Panama-flagged vessel spotted the boats.
EU Navfor said the pirates started chuckingequipment overboard as the chopper approached, and the skiffs tried to escape.
One was seized by a boarding team from DeRuyter, while the other was stopped by a helicopter from the EU Navfor flaghipESPS Mendez Nunez.
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