Private security guards on a merchant ship off the coast of East Africa killed a Somali pirate who was part of a group trying to attack their ship Tuesday, the European Union Naval Force says.

EU Naval Force spokesman Cmdr. John Harbour said Wednesday the killing of the pirate is believed to be the first by a private security team. Merchant ships travelling through pirate-infested waters in the Gulf of Aden and Indian Ocean are increasingly hiring onboard security guards to thwart pirate attacks.

The EU Naval force received a distress call Tuesday and dispatched a frigate that launched a helicopter to help locate the pirates. Seven suspected pirates were found, including one who had died from gunshot wounds. The six remaining suspects were taken into custody.

The naval force has stepped up its enforcement in the waters off East Africa in an effort to thwart a growing pirate trade. Piracy has flourished off the coast of Somalia, which has not had a functioning government for 19 years.

On Tuesday, the EU force said Somali pirates hijacked a Turkish ship with 21 crew on board.

Earlier this week, the EU Naval Force said one of its warships rescued 13 sailors on an Iranian dhow who had been left for dead after a pirate attack.

With files from CBC News