At least four people were killed by a landmine blast in the Yemen's northern oil-rich province of Marib, a military official said.

"A landmine blast occurred in Sirwah district of the government-controlled province of Marib, killing at least four people in the area," the official told Xinhua news agency.

He clarified that the area witnessed bloody fighting between the Saudi-backed Yemeni government forces and the Houthi militia during the past period.

All the killed people were family members and were heading to their farms, according to the official.

Daily explosions caused by landmines and Improvised Explosive Devices (IEDs) target Yemeni people in various areas of the Arab world's poorest country.

Reports by several humanitarian organisations indicated that Yemen has become one of the largest landmine battlefields in the world since World War II.

The Houthis are still launching sporadic military operations against Marib, in an attempt to control the whole strategic province that includes the country's largest oil and gas fields.

Yemen has been mired in a civil war since the Houthi militia overran much of the country militarily and seized all northern provinces, including the capital Sanaa, in 2014.

Saudi Arabia has been leading a military coalition that intervened in Yemen in 2015 to support the government of President Abd-Rabbu Mansour Hadi after the Houthis forced him into exile.