Leading the improvement in Berkshire's insurance operations was General Re and Berkshire Hathaway Reinsurance Group (BHRG). General Re posts a first-quarter underwriting profit of $81 million compared to a loss of $326 million.

BHRG reports a significant reduction in first-quarter underwriting losses: $191 million compared to $1.34 billion after the first three months last year.

Berkshiresays it did not have any significant catastrophe events in the first quarter. Last year, Berkshire recorded pre-tax-catastrophe losses of $1.7 billion from events like earthquakes in Japan and New Zealandand flooding inAustralia.

GEICO,Berkshire's direct private passenger automobile insurer, reports a decrease in first-quarter-underwriting income to $124 million from $337 million last year.

Premiums earned at GEICO increased 9.3 percent to more than $4 billion. However, losses and loss-adjustment expenses during the first quarter increased 10.6 percent to $2.93 billion versus the same period in 2011 due to higher injury and physical-damage severities.

Property and casualty premiums earned in the first quarter at the General Re unit were up nearly 3 percent to $735 million.

“Price competition in most property and casualty lines persists,” says Berkshire in a filing with the U.S. Securities Exchange Commission. “Our underwriters continue to exercise discipline by not accepting offers to write business where prices are deemed inadequate.”

Premiums earned at BHRG declined $55 million, or 29 percent, during the first quarter, but losses from catastrophes were much less than in 2011. The company says it has “generally constrained the volume of business written in recent years as premium rates have not been attractive enough to warrant increasing volume.”