US shares have fallen after the US government said it had launched both criminal and civil investigations into BP's oil leak in the Gulf of Mexico.
The declines came at the end of trading, minutes after Attorney General Eric Holder made the announcement.
Oil services firms led the falls, with Anadarko Petroleum ending down almost 20%, and Halliburton losing almost 15%.
The main Dow Jones index lost 1.1%, while the Standard & Poor's 500 gave up 1.7%, and the Nasdaq fell 1.5%.
Announcing the investigations, Mr Holder said: "We will prosecute to the fullest extent of the law anyone who has violated the law.
"We will not rest until justice is done."
BP shares had earlier finished trading in London down 13% after the firm's latest attempt to halt the leak failed.
The company said it had now started another attempt to stem the flow of oil, but warned that there were no guarantees it would be successful.
Concerns about BP had earlier dragged European share indexes lower in intraday trading, but they subsequently recovered.
The UK's FTSE 100 was down 2.1% at one point, while France's Cac was 2.1% lower, and Germany's Dax down 2%.
Europe's shares hit
However, the FTSE recovered to finish down just 0.5%, while the Cac closed 0.1% lower, and the Dax finished up 0.3%.
Fresh concerns about the impact of excessive European government debt also hit Europe's shares - and the euro.
This came after the European Central Bank warned that it may result in commercial banks have to write off further multi-million euro bad loans.
The euro fell to a four-year low against the dollar at one point, hitting $1.2111, before recovering back up to $1.2266.