The OR Tambo International Airport, outside Johannesburg, was experiencing flight delays on Thursday due to a power outage, it said.
Drugs A Problem: Youth
Spokeswoman Shirley Wakefield said: "It is clear that not only is drug-taking in South Africa a huge problem, but the situation is also seen to be deteriorating, rather than improving."
According to the cellphone survey, of 5024 respondents aged between 13 and 34, 95 percent said they regarded drugs as a problem in South Africa.
Almost two-thirds indicated their belief that police needed to do more to stop the sale and use of illegal drugs.
"These perceptions regarding the problem of drugs and the ineffective policing of the situation were broadly held, across all demographic groups," Wakefield said.
Of those surveyed, 73 percent claimed to know a drug user. For the 13 to 14 age group, two-thirds said they knew someone who used drugs.
"This is a social problem that cuts across all demographic groups, indicating that it is widespread across the country," Wakefield said.
"It is clear that more decisive action is needed urgently."
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