Oil prices fell to two-week lows on Thursday as they extended big losses from the previous session amid a rout in global stock markets, with oil also taking a hit from an industry report showing U.S. crude inventories rose more than expected.

Supply worries also eased as Hurricane Michael likely spared oil assets from significant damage as it smashed into Florida, even as it caused at least one death, injuries and widespread destruction, Reuters said.

Read alsoReuters: Oil dips as IMF lowers global growth outlook; eyes on U.S. hurricane

Brent crude LCOc1 futures were down $1.22, or 1.5 percent, at $81.87 a barrel by 0237 GMT. They earlier touched their lowest since September 28 at $81.61, after closing 2.2 percent lower on Wednesday.

U.S. West Texas Intermediate (WTI) crude CLc1 futures were down by $1, or 1.4 percent, at $72.17, having also fallen to their lowest since Sept. 28. They dropped 2.4 percent in the previous session.

Stocks on major world markets slid to a three-month low on Wednesday, with the benchmark S&P500 stock index falling more than 3 percent, its biggest one-day decline since February.

U.S. crude stockpiles rose more than expected last week, while gasoline inventories increased and distillate stocks drew, industry group the American Petroleum Institute said on Wednesday.

Crude inventories climbed by 9.7 million barrels in the week to October 5 to 410.7 million, compared with analyst expectations for an increase of 2.6 million barrels.