Eleven men were charged Tuesday in a Singapore court over their part in an alleged oil theft at Shell's biggest refinery, court documents showed.

Police in the island-state, Asia's main oil trading hub, said earlier that day they had detained 17 men and seized SG$3.05 million ($2.29 million) in cash and a 12,000-deadweight-ton tanker during their investigations at the Pulau Bukom industrial site.

Royal Dutch Shell PLC, which first reported the theft to authorities in August, said in a news release that the arrests included "a limited number of Shell employees" and that it anticipated "a short delay in the supply operations at Bukom."