Yemen’s Houthi rebels hit a power station in Saudi Arabia’s southern province of Jizan with a “cruise missile”, the group’s Al Masirah TV channel reported.

On Thursday, the Saudi-Emirati-led military coalition in Yemen confirmed Houthi forces fired a “projectile” at a desalination plant in Al Shuqaiq city, but said no one was wounded and there was no damage caused to the facility.

It was not possible to independently confirm if it was a power station or desalintation facility that was hit.

In a statement carried by the official Saudi Press Agency, coalition officials said Saudi security forces were working to determine what type of projectile had been fired.

The attack came after White House officials said US President Donald Trumphad been briefed about a reported strike on the kingdom’s “critical infrastructure”, without giving details of possible damage or casualties.

“We are closely monitoring the situation and continuing to consult with our partners and allies,” White House spokeswoman Sarah Sanders said in a statement.

A Pentagon spokeswoman, Navy Commander Rebecca Rebarich, said such attacks were “a significant cause for concern and [put] innocent lives at risk”.

‘No end in sight’

The Houthis have stepped up missile and drone attacks in Saudi Arabia in recent weeks amid rising tensions throughout the Middle East fuelled by a bitter standoff between Iran and the United States, which is allied to several Gulf Arab states, including Saudi Arabia.

Last week, a missile attack on Saudi Arabia’s southern Abha airport allegedly carried out by the rebel group wounded 26 civilians.

Several other recent drone and missile attacks targeting other southern regions of the kingdom, including Khamis Mushait and Jizan, were intercepted by Saudi forces.

Al Jazeera’s Mohammed al-Attab, reporting from the Yemeni capital Sanaa, said there appeared to be “no end in sight” for attacks and reprisals between Saudi Arabia and the Houthis.

“The conflict is escalating … and according to the Houthis’ military spokesperson, the coming days will witness more surprises for Saudi Arabia, especially via reprisal attacks by cruise missiles and drone operations,” al-Attab said.

Since then, the conflict has killed at least 10,000 people, according to the United Nations, while monitoring group Armed Conflict Location and Event Data Project (ACLED) on Wednesday said 91,600 people have been killed so far.

The war has unleashed what the UN describes as the world’s worst humanitarian crisis, with over 24 million Yemenis – more than two-thirds of the population – deemed to be in need of aid.

Regional tensions rise

Amid the unrest in Yemen, friction has also ratcheted up across the wider region in recent weeks, with Washington and Riyadh blaming Tehran for a spate of attacks on critical oil-related assets and infrastructure, including two tankers in the Gulf of Oman and four ships off the United Arab Emirates (UAE).

Both incidents took place near the Strait of Hormuz, a major conduit for global oil supplies. Iran has denied responsibility for the attacks.

In the latest flashpoint on Thursday, Iran’s elite Revolutionary Guard force said it shot down a US “spy drone” over its territory, according to Iranian state television reports.

An anonymous US official later told news agencies that a US naval drone was downed over international airspace.

In moves it said were aimed at countering Iranian threats, Washington recently deployed additional troops along with aircraft carriers and B-52 bombers to the Middle East.

Despite the rising tensions, the US, Iran and Saudi Arabia have all said they do not want a war to break out in the region.

However, Washington has vowed to continue to pursue its “maximum pressure” campaign against Tehran that was rolled out after Trump’s decision in May 2018 to withdraw from a landmark nuclear deal brokered between Iran and several other world powers, kickstarting increasingly fractious relations.