There were running battles between armed police and vendors at Nchalo Trading Centre in Chikwawa on Tuesday after police carried out an operation to confiscate items suspected to have been stolen.
For nearly three hours, the traders, who were dominated by youths, pelted the police with stones and burned used tyres, according to eye witnesses at the scene.
Motorists travelling on the Chikwawa-Nchalo-Ngabu section of the M1 Road going either side were blocked as the protesters threatened to deal with them, said the witnesses.
Police used teargas to suppress the stone-pelting traders who remained adamant.
Calm returned in the afternoon following the intervention of Chikwawa Central member of Parliament (MP) Zaheer Gaffar Issa who held an impromptu meeting with the traders.
Nchalo Police Sub-station officer-in-charge Eluby Simfukwe said the people were annoyed with the cleaning exercise after some of their colleagues were arrested for possessing items without backing documentation.
She said several items, including 30 bags of cannabis sativa (chamba) weighing 50 kilogrammes (kg) each, cement, iron sheets, gallons of liquor, assorted cables were confiscated during the operation.