Sanaa,  Yemen's Houthi group has said that they have warned a foreign oil tanker not to load crude oil in a government-controlled port in the Yemeni southeastern province of Shabwa.

"We have sent warning messages to the ship in Qana port not to loot oil," Houthi Military Spokesman Yehya Sarea said in a statement on Thursday broadcast by the Houthi-run al-Masirah TV.

Meanwhile, a local security source at the Qana port told Xinhua news agency on condition of anonymity that the port was attacked by Houthi drones on Wednesday, injuring at least five workers and causing partial destruction to the facility.

The source said a ship was waiting at the port for unloading imported oil derivatives to the local markets when the drone attack occurred, adding that the ship had to leave the port without being able to unload its cargo, Xinhua news agency reported.

This was the Houthi group's second attempt in less than a month to conduct drone attacks against government-held ports. On October 21, the Houthis used bomb-laden drones to attack Dhabah port in the province of Hadramout, just hours before the arrival of an oil tanker that was scheduled to export oil from the war-torn country. No casualties were reported in that attack.

The escalation came after the government and the Houthi group failed to extend a national truce that expired on October 2, raising concerns about the return of violent conflicts to the Arab country.

The government said last week that it started to tighten up precautionary security measures around key production facilities and ports in some southern regions.

Yemen has been mired in a civil war since late 2014 when the Iran-backed Houthi militia stormed several northern cities and forced the Saudi-backed Yemeni government out of the capital Sanaa.

The war has killed tens of thousands of people, displaced 4 million, and pushed the country to the brink of starvation.