Police put up barricades at the market’s gates at 4:30 p.m.
Health authorities have collected samples from 150 vendors and managers of the market for testing, advising others and people who have visited the market since July 18 to isolate themselves and inform local health officials.
The market was partially locked down on Sunday after a seafood vendor tested Covid-19 positive.
Long Bien in Ba Dinh District is the fourth wholesale market to be locked down in one week in the capital city, after Phung Khoang, Minh Khai and South.
Hanoi has recorded 1,668 local cases in the fourth Covid wave since late April, with many new clusters detected in the past week.