Residents of Sanaa also report more than 30 Saudi-led air strikes overnight on Houthi targets
Saudi-backed Yemeni forces landed by sea at the Red Sea port of Maydee near the border with Saudi Arabia late on Wednesday, residents said, opening up a new front in a nine-month-old civil war.
Northern Yemen is a stronghold of the Iranian-allied Houthi group, which has seized large parts of Yemen including the capital from forces loyal to the embattled Saudi-backed president, Abd-Rabbu Mansour Hadi.
Hadi's forces attempted to push from Maydee's port, pounded for weeks by air strikes and naval shelling, into the surrounding city, but ran into heavy Houthi resistance and landmines, residents told Reuters by telephone.
Major General Adel Qumairi of the pro-government forces told Saudi-owned Arabiya TV that his forces had "completely taken control" of the city.
But Yemen's state news agency Saba, run by the Houthis, quoted Sharaf Luqman, a spokesman for forces allied to the group, as saying the advance had been met by "heroic resistance" that caused them "great material and human losses".
Residents of Sanaa reported over 30 Saudi-led air strikes overnight on Houthi targets, in one of the capital's fiercest aerial bombardments of the war.
A coalition led by Saudi Arabia and its Sunni Muslim allies has been fighting the Shi'ite Houthi movement to repel what it sees as creeping influence by the group's ally, Iran, Saudi Arabia's bitter rival for influence across the Middle East.
The Houthis deny being under Iran's influence and say they are fighting a revolution against a corrupt government and Gulf Arab powers beholden to the West.
The Saudi spokesman for the coalition, Brigadier General Ahmed Asseri, told Al Arabiya that a Houthi ballistic missile aimed at the kingdom overnight had exploded on launch.
Saudi Arabia on Saturday announced the end of a truce that had reduced fighting but had been repeatedly violated by both sides.