Shiite rebels in Yemen claimed Monday to have shot down a Moroccan F-16 fighter jet taking part in a Saudi-led coalition targeting them and their allies in the Arabian Peninsula nation.
Morocco's military, however, would only say that the jet had gone missing around 6 pm (1500 GMT, 11 a.m. EDT) Sunday.
The purported downing of the jet fighter came as a Saudi-owned news channel, al-Hadath, aired live footage of tanks and armoured personnel carriers loaded onto giant trucks, saying they were part of a "strike force" deploying to the kingdom's border with Yemen. There have been no signs to suggest that a ground offensive was imminent, although the coalition has not ruled one out.
Photos purporting to show the wreckage of the Moroccan aircraft on social media networks had armed tribesmen and children posing next to wreckage that bore the North African kingdom's national colors of red and green. A corpse also was seen.
The claim by rebels, also known as Houthis, was made by their mouth-piece television station al-Masar, saying the plane was brought down in the northern province of Saada.
The rebels and allies in Yemen's splintered armed forces routinely fire anti-aircraft guns at warplanes launching strikes in the country since the Saudi-led campaign began March 26.
Morocco's state news agency MAP, citing a military statement, said the pilot of a second jet said he didn't see the pilot of the missing fighter eject. The military said it had launched an investigation into the incident, without elaborating on a cause.
Morocco has six F-16 jets stationed in the United Arab Emirates taking part in the Saudi-led coalition, which includes a group of other Sunni Arab countries. The West says regional Shiite power Iran backs the Houthis militarily, something both the Islamic Republic and the rebels deny.
If confirmed the Moroccan F-16 would be the second jet fighter to go down in the conflict. During the early days of the air campaign, a fighter jet crashed in the Arabian Sea off Yemen's southern coast, but the pilot and co-pilot were picked up by a nearby navy vessel. Technical problems were said to have caused the crash.
The raging conflict in Yemen has killed over 1,400 people - many of them civilians - since March 19, according to the United Nations. The cease-fire, scheduled to begin Tuesday, would help ease the suffering of civilians in the Arab world's poorest country. Yemenis are suffering from acute shortages of food, fuel and medicine as a result of the bombing campaign as well as a naval, air and land blockade by the coalition.
On Monday, Human Rights Watch said the blockade is keeping out fuel needed for the survival of Yemeni population, contending that it was a violation of the "laws of war".
Yemen, it said, urgently needs fuel to power generators for hospitals overwhelmed with wounded and to pump drinking water. The coalition, it added, must urgently "implement measures for the rapid processing of oil tankers to allow the safe, secure, and speedy distribution of fuel supplies to the civilian population."
All sides in the conflict have warned they will resume hostilities if the cease-fire is violated.
Yemen was expected to be discussed at a Camp David summit later this week between the United States and leaders of six Gulf, US-allied Arab nations, but the kings of Saudi Arabia and Bahrain have said they would not attend.
Meanwhile, the extremist Islamic State group's branch in Yemen has released a video purportedly showing the killing of at least 11 Yemeni army soldiers, who it called "apostates," in the southern province of Shabwa. While it could not be independently verified by The Associated Press, the video corresponded to others released by the extremists and supporters of the group shared it online.
Yemen is home to what US considers to be the world's most dangerous al-Qaida affiliate but a branch of the Islamic State group has recently surfaced in the country, taking responsibility for a wave of suicide bombings in Sanaa earlier this year that killed at least 137 people.
The emergence of an Islamic State branch in Yemen adds yet another layer to the chaos gripping the country and threatens to give an even deeper sectarian slant to the conflict there. Zaydis, followers of a Shiite doctrine that exists almost exclusively in Yemen, account for just under a third of Yemen's estimated 25 million, mostly Sunni people. The Houthis are Zaydis.
In Malaysia, the army issued a statement Monday saying it was not sending ground troops to support the Saudi-led coalition. On Sunday, the state-run Saudi Press Agency reported that a contingent of Malaysian troops arrived at Saudi air bases, without elaborating.
In its statement, the Malaysian military said it based two C-130 transport planes in the kingdom only to "facilitate the safe and smooth evacuation of the remaining Malaysian citizens in Yemen".