It is also unclear as to how the construction of these kind of property was authorized, given the lack of legal framework governing it.

The infected people include two Chinese, four Vietnamese, and one American.

All new cases confirmed on March 11 are related to those who took international flights from or with stopovers in epidemic-hit countries.

So far, eight people have got infected from patient 34, making her the largest source of contagion so far.

The newest case drives up the infection caseload in Hanoi to 7.