At least 25 civilians were killed in rockets shelling in Yemen's Marib province late Friday as ground battles intensified between the Shiite Houthi group and pro-government troops, the media reported.

Medical sources told Xinhua news agency that 25 civilians were killed and more than 16 wounded in the shelling in the market in Marib city, the provincial capital.

Witnesses said Houthi fighters fired Katyusha rockets upon the arrival of Yemeni troops trained in Saudi Arabia on Friday to Marib city.

The troops, which returned to Yemen on Wednesday, came as part of military preparation led by the Saudi-led coalition to take Marib from the Houthis and to advance to the capital Sanaa to restore power of exiled President Abd-Rabbu Mansour Hadi.

Meanwhile, the coalition warplanes bombed a arms depot on a mountain near Yemen's official television in northern Sanaa on Friday, causing huge explosion that rocked the nearby residential areas.

Pro-Hadi troops continued battles on Friday against the Shiite Houthi group and allied forces loyal to former President Ali Abdullash Saleh in Marib province.

The intensified air raids came in the wake of the killing of over 60 coalition soldiers, mostly from the United Arab Emirates, when Houthi rocket fire hit a weapons store at a military camp used by the coalition in Marib last Friday.

The Saudi-led coalition is made up of nine Arab states and has been striking the Houthis across Yemen since March 26, when President Hadi fled to the Saudi capital of Riyadh to take refuge.

More than 4,500 people have been killed in the civil war.