Crude oil futures ended notably lower on Friday and posted a sharp weekly loss as well, as an increase in U.S. crude inventories and concerns about the outlook for energy demand continued to weigh on the commodity.

Traders also took note of a report from Baker Hughes that said the number of active oil rigs in the U.S. declined to 860, the lowest level in nearly 30 months. West Texas Intermediate Crude oil futures for November ended down $0.50, or about 0.9%, at $55.91 a barrel. On Thursday, WTI crude oil futures for November ended down $0.08, or less than 0.1%, at $56.41 a barrel.

For the week, crude oil futures shed about 3.8%. Data showing a drop in China's industrial profits in August amid the trade disputes with the United States raised concerns about energy demand from the world's second largest economy. China's industrial profits declined by 2% year-on-year in August, against a 2.6% jump in July. In January - August, industrial profits dropped 1.7% annually.

The recent Energy Information Administration's report showing a surprise buildup in U.S. crude stockpile last week and reports saying Saudi Arabia has restored its oil production much faster than expected weighed on oil prices. A report from the International Energy Agency indicated a likely cut in growth estimates for global oil demand for 2019 and 2020 in the event of the global economy weakening further.