Royal Dutch Shell is patching an oil leak in a Nigerian crude oil pipeline, the second such incident in recent weeks, that the government says was caused by thieves.

Shell's 70,000 barrel-per-day Nembe Creek pipeline, in the country's swampy river delta, was shut down just before Christmas, Reuters reported Wednesday, after thieves installing valves at two points along the 60-mile pipeline caused the leak.

It is not clear how much oil escaped following this most recent leak, but more than 200 barrels of spilled oil have been recovered, Shell said.

The flow of the 70,000 barrels is partly deferred, and some producing flow stations have been shut to mitigate the spill.

What is really worrying about this leak is that it happened on a facility which was commissioned in October 2009 to replace an old line which was repeatedly targeted by crude oil thieves, said company spokesman Tony Attah. Sadly, the crude thieves continue to hinder efforts to maintain the integrity of key national oil and gas assets.

Before the Nembe Creeke pipeline leaked, a pipeline transporting oil from Shell's offshore facility to an awaiting tanker rupturedon Dec. 20. That pipeline leaked 40,000 barrels into the Atlantic Ocean. Officials say most of the oil has been dispersed.

Shell denies allegations that oil from its offshore facility has reached the country's shores, Reuters reported.

Shares of Royal Dutch Shell fell 16 cents to $74.06 in afternoon trading.