Earlier this week, the militia temporarily released three South Korean vessels and their 16 crew members, including two South Korean nationals, following reports that they had seized a ship carrying a drilling rig from Saudi Arabia to Somalia through the Red Sea.

Yemen's Houthi militia have reported shooting down a Saudi-led coalition F-15 fighter jet.

In a tweet cited by Reuters, a militia spokesman wrote: "Our air defence systems have intercepted an F-15 fighter jet belonging to the countries of aggression in Saada province."

The Houthis did not clarify which coalition country the plane belonged to. The Saudi-led coalition in Yemen includes Saudi Arabia, the United Arab Emirates, Bahrain, Kuwait, Jordan, Egypt and Sudan, as well as proviate military contractors and US and UK logistical and other support. Saudi Arabia and Israel are the only operators of the F-15 in the Middle East.

The Saudi-led coalition has yet to comment on the Houthi claims.

Earlier Wednesday, South Korea's foreign ministry confirmed that all three of its ships and their crew members had been released by the Houthis, who had earlier seized the vessels as they transitted the Red Sea amid speculation that one of the ship was a Saudi-flagged tugboat. The militia claimed they seized the vessels for violating Yemen's territorial waters.

Wednesday's alleged incident wasn't the first time the Houthis have reported attacking an F-15. Last year, the group claimed that they shot down a Royal Saudi Air Force F-15. The group later released footage of a plane being struck by a surface-to-air missile while launching flares. In March 2018, the Saudi air force confirmed that a SAM had been launched at one of its fighters, but said the fighter managed to return to base and land safely.

In addition to fighters, the Houthis have repeatedly reported attacking and downing Saudi coalition drones. The coalition has confirmed some of these incidents.

Saudi Arabia and a coalition of mostly Gulf allies began a military intervention in Yemen in March 2015 at the request of Yemeni President Abdrabbuh Mansur Hadi, who had been ousted from power and fled to the kingdom earlier that year. After over four years of fighting, the coalition has yet to dislodge Yemen's Houthi militia from most of Yemen's population centres, and the Houthis have recently begun launching drone and missile attacks against targets inside Saudi Arabia. In September, the Houthis claimed responsibility for an attack on two major Saudi Aramco oil facilities, which temporarily knocked out half of Riyadh's energy production. Before that, the group launched drones and missiles at military bases, airports, power generation facilities and population centres. Saudi air defences reported downing most of these attacks.

The war in Yemen has led to the deaths of up to 91,000 people, and caused a massive humanitarian crisis.