New Delhi: Several refineries, processing plants and installations remained closed Wednesday, the first day of the indefinite strike called by officers of public sector oil firms, even as the Delhi government arrested an employee under the Essential Services Maintenance Act (ESMA).

The 45,000-strong Oil Sector Officers Association (OSOA), representing 14 organisations, called for the strike from 6 a.m. Wednesday, demanding higher wages.

A senior Indian Oil Corp (IOC) official said all its refineries were impacted at various degrees, but added: "Our workers and officers above the deputy general manger levels have not gone on strike."

The employees went ahead with the strike despite a restraint order from the Delhi High Court.

Narendra Goyal, an office-bearer of the OSOA, was arrested early Wednesday by Delhi Police under the ESMA.

Reports from various installations showed that the strike has affected facilities across the country.

"Most of the refineries of these oil PSUs (public sector undertakings) are either shut down or in the process of being shut down," S. Arunachalam, regional secretary of Indian Oil Officers' Association, eastern region, said in Kolkata.

While IOC said most aviation stations were working, some flights may have been delayed by 30-40 minutes over fuelling issues.

An official at the upstream major Oil and Natural Gas Corp (ONGC) said its gas processing plants at Uran and Hazira have been affected. "There has been no shift change which usually occurs at 8 a.m., so nobody has reported to work," he said.

ONGC's subsidiary Mangalore Refinery has also been affected by the strike, with officials striking work. But, sources inside the refinery said several units were still working.

GAIL India Ltd has also been impacted by the indefinite strike, with reports that supplies of natural gas has stopped at its Hazira plant, its largest gas processing facility.

The Hazira-Bijaipur-Jagdishpur gas pipeline has also been shut down.

According to sources, the Gujarat government has alerted Gujarat Gas, Gujarat State Petroleum Corp and Adani Energy to fulfil demand in case of supply disruption. Similarly, the petroleum ministry has also alerted Reliance and Essar, who have refineries in Jamnagar, to supply petroleum products to distribution companies, if the strike persists.

The consumers will only start feeling the pinch once the retail outlets finish the sales of their present stock, which is expected to last about five to seven days. But, no panic buying has been reported so far.

"We have not experienced any panic buying in our petrol/diesel vending unit at least till now. As usual our clients are filling up their tanks with fuel in their vehicles," said E. Shanmugham, who manages a fuel-vending unit in central Chennai.

Chennai Petroleum Corp (CPC) officials said their company was ensuring supplies despite the strike. "Our supplies are going out almost uninterrupted. The local police have accorded security to our convoys," a CPC official said.