In south Yemen, local authorities ban qat, a mild narcotic

Southern Yemen's local authorities on Monday banned the selling of qat, a plant whose leaves are chewed for a stimulant effect, a widespread tradition among Yemeni men.

Forces loyal to Yemen's internationally recognized government also barred hundreds of qat-ferrying vehicles from entering the southern port city of Aden, and also said they would allow qat chewing only on Thursdays and Fridays, the local weekend. They claimed traffic surrounding the busy and overcrowded qat markets obstructs normal life as well as security operations.

It's the first time a ban on qat has been imposed anywhere in Yemen, though it's unclear how it could be enforced amid the chaos of the country's civil war.

In Aden, merchant Abdu Hazaa said security forces set fire to some of his qat stock but that he managed to smuggle the rest to the black market where it will be sold for a higher price.

The decision could impact qat plantations in northern Yemen, where most of the plant is grown. It comes also amid heightened tensions between the country's northerners and southerners. There is a growing but fractured secessionist movement in the south, demanding the region break away from the north, with which it was united in 1990.

Over the past weeks in the south, pro-government forces detained and evicted residents originally from the north. Armed groups went door to door, raiding and arresting more than 2,000 northerners they claim pose a threat to "security."

Aden was among the first cities from which forces of the internationally recognized government drove out Shiite rebels known as Houthis as part of Yemen's war pitting government forces, backed by a Saudi-led coalition, against the rebels and their allies.