Net earnings for Pittsburgh-based PNC Financial Services Group Inc. fell 32.6 percent to $546 million in the second quarter of 2012.

Earnings for PNC, one of the largest banks operating in Erie and Crawford counties, were down $811 million from the same quarter in 2011.

PNC, which issued its earnings report this morning, said $284 million in residential mortgage repurchase obligations contributed to the lower earnings figure.

“PNC’s results for the second quarter reflected strong operating performance in a challenging environment,” James Rohr, the company’s chief executive, said in a statement.

Highlights for the most recent quarter included net interest income of $2.5 billion, an increase of 10 percent.

Earnings for the first half of the year were $1.4 billion, down from $1.7 billion in the first six months of 2011.