DEARBORN, Mich. — Ford Motor shares tumbled Thursday after it reported weaker-than-expected second-quarter earnings and warned that things could get worse in the second half of the year.

Ford’s net income fell 9 percent to $2 billion in the second quarter as the company struggled with flattening U.S. sales and a tougher market in China.

The Dearborn, Mich.-based company said its full-year guidance — which calls for a pretax profit of $10 billion to $11 billion — remains intact but is at risk. Among the looming issues in the second half of this year are the expensive launch of Ford’s new aluminum-sided Super Duty pickup truck and an expected $145 million hit to sales in Britain because of its vote to leave the European Union.

The automaker’s shares fell $1.13, or 8.2 percent, to finish at $12.71 Thursday.

Ford CEO Mark Fields said the company will take actions to improve its results, including cutting production to meet demand and making sure all markets have the right mix of vehicles.

“It’s kind of like when you’re having a bad golf game you just play through it,” he said.

It wasn’t the result many had expected. After Ford’s chief rival General Motors reported last week that its second-quarter profit more than doubled to $2.87 billion, many analysts thought they’d hear similar good news from Ford.

There was some good news. Because of its strong first quarter, Ford still managed to post a record first-half operating profit of $6.8 billion. In Europe — long a trouble spot — second-quarter sales rose 11 percent and pretax profits nearly tripled to $467 million, thanks in part to stronger sales in Russia.