An oil pipeline pumping station has been attacked in the central Yemeni province of Ma'rib, with the country's warring sides blaming each other for the incident.
Sources close to the Saudi-backed former regime in Yemen on Sunday accused Yemen's Houthi fighters of targeting the station, according to the Saudi state news agency (SPA).
Hussein al-Ezzi, an official in the capital Sana'a, said Saudi-backed militants had attacked the Kofel pumping station in what he described as a dangerous escalation.
The pipeline is operated by Saudi-backed Safer oil company but no oil has been pumped through it for years.
Yemen's oil output has collapsed since 2015 when Saudi Arabia intervened in Yemen to try to restore the government of former president Abd Rabbuh Mansour Hadi to power after he resigned and later fled to Riyadh.
Yemen's armed forces are seeking to liberate Ma’rib after taking control of the neighboring strategic province of al-Jawf, which borders Saudi Arabia.
The Yemeni ground advancements come amid clashes between UAE-backed southern separatists and Saudi-led mercenaries in Aden.
On Friday, the former governor of Yemen’s southwestern Ta'izz province said that the United Arab Emirates is manipulating the demographic composition of the province to weaken pro-Saudi forces, exposing further rift in the Saudi-led coalition.
“Forces affiliated to the UAE have rented certain homes in the coastal areas of Tai’zz and are financially supporting certain individuals who seek to overthrow the [Saudi-installed] government,” Ali al-Moamari was cited by Al-Jazeera as saying.
The UAE joined Saudi Arabia in 2015 in the war seeking to install the pro-Saudi former president Hadi and crush the Yemeni popular Ansarullah movement.
However, with the Saudi-led campaign being brought to a standstill due to the Yemeni resistance, widening rifts have emerged between Saudi-led mercenaries loyal to Hadi and UAE-affiliated forces.
Tensions reached a climax last summer when months of bloody infighting broke out, resulting in heavy casualties between the two sides before a power-sharing settlement was signed in November.
Blast hits Saudi-backed forces in Aden
London-based al-Araby al-Jadeed newspaper reported that a booby-trapped explosion targeted Saudi-backed forces in Aden on Sunday.
The attack occurred when a convoy of Saudi armored vehicles was on its way from Aden international airport to the headquarters of coalition forces.
No casualties were reported, but the blast destroyed a Saudi armored vehicle.
The paper said that the attack was the first military action against Saudi forces since they were replaced by Emirati forces in October.
No individual or group has claimed responsibility for the attack.
Both the UAE-sponsored separatists and the Saudi-backed militants loyal to Hadi serve the Riyadh-led military coalition and have been engaged in a bloody war on Yemeni people since March 2015.
Ties between the two sides have soured over a number of issues, including what the Yemenis view as the UAE's intention to occupy Yemen’s strategic Socotra Island and gain dominance over major waterways in the region.
The US-based Armed Conflict Location and Event Data Project (ACLED), a nonprofit conflict-research organization, estimates that the Saudi war on Yemen has claimed more than 100,000 lives over the past nearly five years.
Saudi Arabia and the United Arab Emirates have purchased billions of dollars worth of weapons from the United States, France and the United Kingdom in their war on Yemen.
The UN says over 24 million Yemenis are in dire need of humanitarian aid, including 10 million suffering from extreme levels of hunger.