Most of the locally transmitted cases were documented in quarantine or lockdown areas in southern localities.
Ho Chi Minh City took the lead, registering 354 new cases over six hours, followed by Binh Duong 195, Dong Thap 50, and Long An 46.
Elsewhere 32 cases were recorded in Phu Yen, six in Da Nang, four in Bac Giang and one or two cases in several other central and northern provinces.
Meanwhile, eight Vietnamese people returning from overseas, including Indonesia and Japan, have tested positive in Kien Giang, Khanh Hoa, Binh Dinh and Ninh Binh during the past six hours.
The fresh coronavirus outbreak has shown signs of waning in the north, but new cases are surging in southern and central regions.
Many cases were closely linked to returnees from HCM City, who had been labelled as COVID-19 patients.
Data from the Ministry of Health show Vietnam has detected 1,945 locally transmitted and eight imported cases from 06.00am July 10 to 06,00pm July 11. It was a new record Vietnam has set after logging 1,853 cases the day before.
HCM City, the largest coronavirus hotspot, registered 1,397 cases alone, followed by Binh Duong 234 and Dong Thap 50.
As of 06.00pm July 11 Vietnam has documented 26,322 new cases during the fresh outbreak in 58 cities and provinces and a total of 29,816 cases since January 2020.
As many as 9,275 patients have recovered from the disease, and 119 patients have died of COVID-19 and other underlying illnesses.
More than 4 million doses of the vaccine have been administered nationwide, with 271,409 people fully receiving two shots.
In other developments:
- Centrally-run Can Tho city imposes social distancing as of July 12
- PM Pham Minh Chinh inspects COVID-19 prevention in HCM City
- The Health Ministry dispatches a contingent of doctors to Dong Thap
- Hanoi detects 11 more cases returning from HCM City, Da Nang