Three Somalian pirates have admitted hijacking an American yacht and killing its four crew.

Mohamud Hirs Issa Ali, 32, Mohamud Salad Ali, 35, and Ali Abdi Mohamed, 35, will avoid the death penalty, but face life imprisonment after pleading guilty in an American federal court.

11 other Somalis and a Yemeni have also been arrested in connection with the killings of Jean and Scott Adam, Bob Riggle and Phyllis Macay in February.

At the time Mr and Mrs Adam (pictured), who owned the Davidson 58 pilot house cutter, Quest, were sailing around the world, distributing Bibles to schools and churches in remote destinations en route.

Several days after being taken hostage the four were shot to death, as US Navy officials negotiated with the pirates.

The US military said that the pirates’ negotiations were lead by Mohammad Saaili Shibin, who has also been indicted over the murders.

A prosecutor’s statement said that Mr Issa Ali and Mr Salad Ali acknowledged ‘that they served as leaders of the piracy operation’.

The pirates are said to have possessed weapons, including a grenade launcher and assault rifles, at the time of their arrest and Mr Abdi Mohamed admitted ‘that he fired a rocket propelled grenade in the course of the crime’.

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