HONG KONG -- The government of China's Hong Kong Special Administrative Region appealed on Wednesday that all students "must put safety first at all times" in the light of the current traffic and emergency conditions.

"They must not wander on the streets or go to potentially dangerous places, and should never participate in unlawful activities," said the Education Bureau of the HKSAR government in a statement.

The bureau urged schools to keep their premises open, take proper care of students who have arrived at school, maintain communication with parents, and allow students to return home only under safe conditions.

Parents can decide whether to send their children to school and should notify the school of their decision as soon as possible, the bureau noted.

On the same day, the Labor Department also issued a statement urging employers to make flexible work arrangements if employees are unable to work on time due to disrupted road traffic or public transport services.

Tensions have escalated over the past few days as rioters attempted to paralyze traffic in Hong Kong by trashing transport facilities and obstructing roads, which have seriously affected commute and traffic.

Roads at as many as 50 locations were damaged or obstructed and over 160 traffic lights smashed, said the police. Rioters threw objects such as petrol bombs and bicycles on subway tracks and punctured tires of buses, trying to bring the traffic to a standstill.