Boston-based insurer Liberty Mutual Group has reported third-quarter net income of $6 million, compared to $404 million in the same period last year, a 98.5 percent decease.

Year-to-date, net income was reported at $666 million, compared to $1.093 billion in the same period in 2007.

“Given the circumstances, we are pleased with our results in the third quarter,” said Edmund F. Kelly, chairman, president and chief executive officer of Liberty Mutual Group. “We absorbed over $800 million of pre-tax natural catastrophe losses and approximately $250 million of pre-tax investment losses and still reported positive, albeit slightly, results in the quarter. The fundamental strength of our business has never been more apparent.”