Factbox - Oil sands production shuttered by northern Alberta wildfires

CALGARY, Alberta (Reuters) - Two separate wildfires have shuttered oil sands operations in northern Alberta, forcing producers to halt hundreds of thousands of barrels per day of production.

A blaze in the Wabasca region discovered on Tuesday prompted Cenovus Energy and Canadian Natural Resources Ltd to shut in 23,800 barrels.

Meanwhile oil companies are restarting operations in the region around Fort McMurray, Alberta, following a huge wildfire last month that forced many sites to evacuate as a precaution.

At its height, the shutdown at major oil sites cut daily production by more than 1 million barrels. At least 400,000 barrels per day of production is still offline although in reality that number is likely far higher as many producers are still in the process of ramping back up to normal rates. In addition, Suncor Energy's base plant and the Syncrude project still need to finish maintenance turnarounds interrupted by the fire.

(Reporting by Barani Krishnan in New York, Ethan Lou, Euan Rocha and Jeffrey Hodgson in Toronto, Nia Williams and Eric M. Johnson in Calgary; Compiled by David Gaffen and Josephine Mason; Editing by Chris Reese and James Dalgleish)