WARREN, N.J.—The Chubb Corp. posted a 10.1% increase in net income for the first half ended June 30, to $982 million.

Results reflect $217 million in pretax net realized investment gains, compared with $239 million in losses for the comparable period a year ago, said the Warren, N.J.-based insurer.

There were $537 million in pretax catastrophe losses in the quarter, compared with $69 million of such losses in the first half of 2009.

In its property/casualty operations, Chubb reported a 92% combined ratio vs. an 87% combined ratio for the same period a year ago.

Net premiums written increased 1.1%, to $5.65 billion.

For the second quarter, Chubb reported a 6% decline in net income, to $518 million. This reflected $193 million in pretax catastrophe losses, compared with $43 million in 2009’s second quarter.

Chubb reported a 90.4% combined ratio for the quarter vs. an 85.9% combined ratio for the same period a year ago.

Net premiums written for the quarter increased 1.4%, to $2.89 billion.