Twitter and the Huffington Post UK confirmed they were hacked after the Syrian Electronic Army made claims it had taken over the sites.
Twitter said the hack led to availability issues for an hour and a half but that no user information was compromised.
The Huffington Post attack was limited to the blogging platform's UK web address, a spokesperson said.
The attacks came as the Obama administration considers taking action against the Syrian government.
More top news
It comes in contrast to other major European countries including Germany, France and Spain where growth exceeded expectations.
Nine people have died and several are in hospital after being discovered in the back of a lorry in a car park in Texas.
The parents of the terminally-ill 11-month-old say there is new evidence they hope will persuade a judge to change his mind.