(Reuters) -Shell has shut down an oil processing unit at its Pulau Bukom facility to investigate a suspected leak, Singapore’s Maritime and Port Authority (MPA) and National Environment Agency (NEA) said on Friday.

The oil company estimates that a few tonnes of refined oil products, along with cooling water discharge used in the refining process, have leaked.

Pulau Bukom, site of Singapore’s first refinery, now houses Shell (LON:)’s only energy and chemicals park in Asia, according to the company’s website.

Shell confirmed in an emailed statement to Reuters that oil sheens were spotted alongside a wharf on Dec. 26, 2024 at Shell Energy and Park Singapore.

The company stated it has taken steps to contain the leak and prevent it from spreading into the sea and has deployed boats alongside the MPA to clean up light oil sheens observed near the leak site.

The MPA said investigations are ongoing, and navigation traffic in the area remains unaffected.