Europe's largest debt collector Intrum reported smaller-than-expected operating earnings for the second quarter on Thursday, while it said margins in its key servicing segment had improved in the period.

Its adjusted operating profit fell 15% to 1.25 billion Swedish crowns ($118.47 million) from 1.47 billion crowns a year ago. That missed analysts' expectations of 1.37 billion crowns, a company-provided poll showed.

Removing discontinued operations, mainly related to the sale of a large portion of its investment portfolio to Cerberus which closed earlier this month, operating profit stood at 1.02 billion crowns.

Intrum shares have taken a 45% hit since the start of the year, with investor concerns mounting over the manager of bad loans' own debt pile, which stood at 49 billion crowns at the end of June.

Profit margin in its servicing segment, a key business area as Intrum aims to grow earnings from collecting debt owed to others, was 19% in the quarter, above the 16% expected by analysts, and also higher than the margin of 16% a year ago.

"The second quarter was characterised by continued progress to improve our financial profile, continued margin development in Servicing, and advancements in our pivot toward a capital-light business model," CEO Andres Rubio said in a statement. ($1 = 10.5512 Swedish crowns)

(Reporting by Greta Rosen Fondahn; Editing by Christian Schmollinger and Mrigank Dhaniwala)