A Saudi army general has been killed in cross-border fire from Yemen, the armed forces announced Sunday, making him the highest-ranking officer to be killed in border attacks since March.

Major General Abdulrahman bin Saad al-Shahrani, commander of the 18th Brigade, was inspecting troops deployed "on the front lines along the southern region when the post came under random enemy fire," said the military said in a statement carried by the official SPA news agency.

Shahrani was wounded in the attack and hospitalised, it said.

The statement did not say when the attack occurred but added that Shahrani had died of his injuries on Sunday.

Earlier, the SPA reported that a Saudi border guard had been killed on Saturday by a rocket fired from Yemeni anti-government rebels that hit a border post in the kingdom's Hazan region.

More than 50 people, most of them troops, have been killed along the Saudi-Yemen border since the Riyadh-led military coalition began air strikes on Iran-backed rebels across the kingdom's impoverished neighbour in March.

But Shahrani is the most senior Saudi officer to be killed in cross-border fire.

Al-Qaeda in Aden

The killing follow the alleged capture of a western district of Yemen's main port city of Aden by al-Qaeda over the weekend.

Eyewitnesses claimed that al-Qaeda flags had been placed over administrative buildings in the city.

"Dozens of al Qaeda militants were patrolling the streets with their weapons in total freedom in a number of areas in Tawahi. At the same time, others raised the al Qaeda black flag above government buildings," a resident told Reuters.

Senior officials have denied, however, that al-Qaeda was in control of any part of the city.

"What's happening there relates to a bunch of lawless gunmen who do not constitute any danger to the city of Aden," Yemen's Deputy Interior Minister Brigadier General Ali Nasser Lakhsha told Reuters. "Their behavior shows they don't belong to al Qaeda and that they are trying to achieve narrow, self-interested goals."

Four suspected al-Qaeda militants were allegedly killed over the weekend in a US drone strike in Mukalla, the city in south Yemen that the group overran in April.

Al-Qaeda in the Arabian Peninsula (AQAP) have used the security vacuum created since protests against the government of former President Ali Abdullah Saleh in 2011 to expand their influence in Yemen.

Four suspected Al-Qaeda militants were killed overnight in an apparent US drone strike in Mukalla, the southern Yemeni city that the extremist group overran in April - See more at: http://www.alaraby.co.uk/english/news/2015/8/23/four-qaeda-suspects-killed-by-drone-strike-in-yemen#sthash.eAAdcrqo.4C3HcRyx.dpuf