A Somali pirate chief has vowed to target Americans in revenge for the death of three pirates killed during a US raid to free an American hostage held by the pirates.
Abdi Garad said on Monday that the US forces had shot and killed the men, even after they had agreed to free the hostage.
"The American liars have killed our friends after they agreed to free the hostage without ransom," Garad was reported by the AFP news agency as saying.
"But I tell you that this matter will lead to retaliation and we will hunt down particularly American citizens travelling our waters."
The news agency reported that Garad was speaking by phone from Eyl, a pirate base on Somalia's eastern coast.
Navy snipers on the USS Bainbridge shot and killed three of the four pirates holding hostage Richard Phillips, the captain of a ship the pirates had attacked.
The pirates had attacked the US-flagged container ship the Maersk Alabama and while the crew seized back the ship, the pirates kept hold of Phillips, the ship's captain, on a lifeboat.
He reportedly jumped from the vessel in an attempt to escape, but was quickly re-captured.
The Bainbridge was one of two US navy warships sent to the scene to monitor the situation and rescue Phillips, a plan approved by Barack Obama, the US president.
The US navy said the snipers opened fire when Phillips' life appeared to be in danger.
"They were pointing the AK-47s at the captain," Vice Admiral William Gortney, head of the US naval central command, said in a Pentagon briefing from Bahrain.
"The on-scene commander took it as the captain was in imminent danger and then made that decision and he had the authorities to make that decision and he had seconds to make that decision," he said.
Before the raid, the pirates, who demanded a $2m ransom for Phillips, warned the US government not to use force.
Meanwhile, the Maersk Alabama arrived in the Kenyan port of Mobassa on Saturday.
Abdulkadir Walayo, a Somali government spokesman, hailed the operation.
"I hope this operation will be a lesson for other pirates holding the hostages on the ships they hijacked," he said.
The raid occurred only two days after French commandos stormed a yacht to rescue two French couples and a child being held by Somali pirates in a separate incident.
Hijackings are an ongoing problem in the busy shipping lanes off the coast of Somalia.
At least a dozen ships have been seized in the Indian Ocean and more than 200 crew members are being held hostage.