The words of Garaad Mohammed, a man we believe to be a pirate with a history of successful hijackings, may well be crude rhetoric designed to add leverage to ransom negotiations.

His willingness to talk to the press comes amid a difficult set of negotiations over one vessel and wider suggestions that pirates are finding it increasingly difficult to extract larger sums from owners.

His words, however, should not be dismissed as an idle threat. Until recently crews held hostage in Somalia have been treated as well as could be expected under the circumstances. Pirates are not terrorists, and the business of extracting ransoms had not previously necessitated violence.

Talk of revenge attacks was touted in the wake of the Maersk Alabama stand-off with US forces, which resulted in three pirates being shot dead by snipers, but these threats did not result in any noticeable escalation of violence.

Nevertheless, fresh evidence that some crew have been returned with injuries and have reported aggressive behaviour is being taken seriously by NATO security officials.

The fact that pirates are now willing to claim responsibility for the death of one seafarer, whether true or not, indicates that they are prepared to use the threat of violence to increase the pressure on the industry.

While the words of one unidentified pirate do not fundamentally alter the threat level in the region and should not colour shipowners’ negotiations, the threat of violence is an unwelcome factor that must now be at least taken into consideration.