WASHINGTON: Twitter shares took a pounding Thursday after the short messaging service reported weaker-than-expected earnings and disappointing user growth. Profit in the first quarter was $68 million, which contrasted with a loss of $8 million in the same period a year ago. Revenues grew 28 percent from a year ago to $1.04 billion but the key figure of “average monetizable daily active users” was below expectations at 199 million, an increase of 20 percent from a year ago.

Twitter shares sank as much as 11 percent in after-hours trade as the results fueled concerns that the platform is not growing fast enough in the rapidly shifting social media space. The company called the results “a solid start” to the year showing growth in ad revenues.

The shares were also hurt by weaker guidance for the coming quarter for Twitter, which has struggled to expand beyond its core audience of celebrities, journalists and political leaders, even if it has become an important forum for policy debates.