Liberty Mutual Holding Co. Inc. posted significantly lower net income due to lingering losses caused by Typhoon Jebi and unfavorable loss trends in liability lines.

The Boston-based mutual insurer reported net income of $399 million in the second quarter of 2019, compared with net income of $981 million in the same period last year, according to its second-quarter earnings statement released Thursday. Net income for the first six months of 2019 was $1.07 billion compared with $1.63 billion during the same time period last year.

Typhoon Jebi was one of the most costly typhoons in Japan’s history, with insurers and reinsurers such as Hiscox Ltd. and Swiss Re Ltd. reporting the financial impacts during the recent round of earnings reports.

The industry loss from Jebi is pegged around $12 billion, and Liberty Mutual has reserved $82 million for Jebi losses, with business interruption and other losses driving those figures higher, Liberty Mutual officials said during the insurer’s earnings conference call on Thursday.

Liberty Mutual’s combined ratio deteriorated to 101.2% in the second quarter of 2019 from 97.9% in the same period of 2018, according to the earnings statement. The combined ratio slightly worsened to 98.7% for the first six months of 2019 from 98.5% in the same period last year.

“Rates were up double digits in commercial auto, property and general liability and in single digits in all other lines except for workers compensation, where the low, negative single-digit rate is generally consistent with what we’re observing across the market,” David H. Long, Liberty Mutual chairman and chief executive officer, said during the call. “While trends in liability lines remain elevated, the rate we’ve taken through the first half of the year has been in excess of observed loss trends by about one to two points. That said, more rate is needed on these lines.”

Net written premium for the second quarter of 2019 was $10.04 billion, a 0.3% decrease from the same period last year, according to the earnings statement. Net written premium for the first six months was $19.74 billion, up 1.2% over the same period in 2018.

“We’re benefiting from several tailwinds across our business evidenced by the increase in rate environment, strong investment results and favorable expense trends,” Mr. Long said. “That said, there are certain segments of our industry, mainly commercial auto and general liability, including excess and umbrella lines, that remain challenged, and it will take time for recent rate increases to materialize through earnings.”

“We will outpace the trends,” he added. “It’s just going to take us longer to get to where we need to get to.”

Ironshore Inc. acquisition and integration costs for the second quarter of 2019 were $6 million, a 40% decrease from the same period in 2018, according to the earnings statement.