A freight train derailment that spilled more than 150,000 litres of sulphuric acid into a northern Ontario river last week is expected to halt rail traffic along the line until at least Thursday.

Twenty-two cars of the 33-car Ontario Northland train jumped the tracks Friday about 215 kilometres north of North Bay.

The incident spilled the equivalent of a tanker load of sulphuric acid into a creek that feeds Blanche River, about 10 kilometres north of the town of Englehart.

Beverly Martin of Ontario Northland said the spill was contained Sunday and lime is being put into the creek upstream of the spill to neutralize the acid.

Martin said the company will use buses to handle passengers who travel on the company's Northlander train between Toronto, Cochrane and North Bay.

Municipal and private water wells haven't been affected by the spill, but people are being warned not to drink from the river or allow their animals or livestock to drink from it as a precaution, Timiskaming health unit spokeswoman Carol Gaulthier said.

With files from the Canadian Press