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Yemen's Houthi rebels have resumed attacks, claiming fresh strikes on three vessels on Monday – two in the Arabian Sea and one in the Red Sea.
In the latest attacks, the group claimed the ships were bound for ports in Israel. All three vessels were Liberia-registered, and one was heading for Shanghai according to Reuters, which cited London Stock Exchange Group data.
One of three vessels attacked, the SC Montreal, was also on its way to Salalah, Oman, from the Seychelles. Another ship, the Maersk Kowloon, had departed Salalah.
The Iran-backed militia has mounted fewer attacks on shipping since around October 18, when they launched a suspected drone attack on a vessel, according to data compiled by the Washington Institute for Near East Policy.
Since then there have been several incidents, including threatening approaches by small boats of the kind used by the Houthis, says the UK Maritime Trade Operations that liaises between merchant vessels and military forces in the region.
The militants claim to attack ships with links to Israel and its supporters, as part of their pressure campaign over the war in Gaza. But most vessels targeted have no link to Israel or the conflict, and their campaign has disrupted food aid to some of the world's poorest countries - including Yemen.
Recorded attacks on shipping in September were also historically low, according to Acled, a conflict-monitoring organisation that also compiles attack data.
One source closely tracking the crisis told The National attacks have dropped to three per month in September and October. That stands in stark contrast to the start of the group’s campaign in November, which involved a helicopter operation to seize a cargo ship and its crew, the Galaxy Leader, and waves of drone and missile attacks, with several involving 20 drones or more.
Michael Knights at the Washington Institute for Near East Policy, by contrast, noted how the group completed 11 attacks against shipping in August. He warned that last month, the group was still capable of firing salvoes of missiles - in one incident targeting a US warship on September 27.
Experts differ on why the group's attacks have seen significant peaks and troughs, with different theories suggesting shortages of munitions, including drones, or weakening co-ordination with their Iranian backers, who previously provided intelligence to the group on which ships to target using a “spy ship” in the Red Sea.
Mr Knights, in a recent report, warned the group still has maritime supply channels from Iran and says the group is likely to sustain attacks despite setbacks.
But two Israeli attacks wrecking oil and energy infrastructure in Hodeidah, and a recent massive US airstrike on underground weapons storage, might also have shaken the militia.
"Houthi leadership are clearly worried about being targeted and appear increasingly isolated in their decision making. Israel and the West have made the consequences of targeting civilians and shipping very clear," one Western diplomat told The National on background.
"Houthis are desperately trying to distract the population from the costs of fighting a foreign war. The port in Hodeidah took extensive damage in the last round of fighting with Israel. There are signs this is fraying relationships," the source said.
The diplomat said the Houthis were imposing increasingly draconian measures on the population, "heavily cracking down," on anyone accused of celebrating the 1962 Northern Yemen independence day, which was marked before the group seized much of the north of the country.
"There’s also little support for the new edicts restricting weddings. Despite a good social media game, the Houthi leadership looks increasingly desperate, under pressure and without an endgame."
US heavy bomber strike
In the absence of targeting information, many ships with no connection to Israel – and some ships linked to sympathetic countries, such as Russia – have been struck.
Whether a shortage of munitions or a change in tactics is responsible for the three month decline in attacks, intense US air strikes on the group on October 18 could have further changed their operations.
Strikes against the group using B-2 bombers hit “five hardened underground weapons storage locations,” according to the US Department of Defence. The strikes, using powerful 1,360 kilogram “bunker-busting” bombs, were far more powerful than previous US strikes on the group, which have involved aircraft carrier-based jets and cruise missiles.
Yemen's Houthis said they will continue these actions until Israel halts its offensive on Gaza and Lebanon. This poses significant risks to commercial shipping in the region, a critical route for global trade linking the Red Sea to the Gulf of Aden.
