Scores of filling stations in South Africa were out of petrol on Thursday due to strikes, raising concerns about a fuel shortage that could hit Africa's largest economy.
Tens of thousands of workers in the sector began walking off the job on Monday, delaying fuel deliveries and sparking panic buying at service stations in the country's economic hub of Gauteng province, which includes Johannesburg.
Refineries were still operating and petrol was being delivered to most petrol stations, indicating no immediate economic damage, but a prolonged and widening strike could hurt the transport sector and prospects for growth.
The Fuel Retailers Association said more than 150 service stations in Gauteng had run dry by close of business on Wednesday.
"The situation is worsening and if we don't manage it properly, we might end up with a crisis next week," said Reggie Sibiya, the FRA's chief executive officer.
Many deliveries were hampered by intimidation from striking workers at depots, producers said.
Unions and employers are locked in their mid-year bargaining session known as "strike season", with many labour groups seeking wage increases that far exceed inflation.
The Solidarity union, which represents about 6,000 skilled workers, on Thursday joined the strike by about 70,000 workers mainly from the Chemical, Energy, Paper, Printing, Wood and Allied Workers Union (CEPPWAWU).
CEPPWAWU members stopped work on Monday, demanding 13 per cent wage increases, about triple the inflation rate, and above the 4 to 7 per cent offered by employers. Other, smaller unions have also joined the strike.
At a Caltex station near Johannesburg's financial district of Sandton, Debbie Edery said after topping up her tank: "It's disastrous. My husband had to leave his office today to go look for petrol. I don't know how we will get to work next week".
CEPPWAWU has said the strike will run into next week and no talks are planned.
Employers in the sector include BP PLC , Royal Dutch Shell PLC , petrochemicals group Sasol Ltd. , state-owned energy group PetroSA, Chevron Corp. and Total SA .
Central bank and Treasury officials have said high wage increases threaten the outlook for inflation and the long-term prospects for the economy.
A strike in the steel and engineering sector entered its second week on Monday, with the industry expecting substantial production and financial losses.
The National Union of Metalworkers of South Africa (NUMSA) and employers in the sector are considering a compromise proposal put forward by the bargaining council, hoping they can avert the strike going into a third week.
Possible strikes also loom in South Africa's platinum, coal and gold industries.