Arch Insurance Group announced the establishment of two principal underwriting groups in its U.S.-based operations: the Arch Property & Casualty Group and the Arch Financial & Professional Liability Group.

The two new groups are designed to help Arch Insurance, a division of Bermuda-based Arch Capital Group Ltd., maximize underwriting opportunities as the market transitions, according to the company. Arch Insurance is headquartered in New York, N.Y., with an operations center located in Jersey City, N.J.

Michael Murphy was promoted by Arch Insurance to president of the Property & Casualty Group. Murphy, who joined the company in 2002, has 20 years of specialty lines experience and served most recently as a senior executive vice president of Arch Insurance.

To head the Financial & Professional Liability Products Group, Arch Insurance has added David McElroy. He recently headed Hartford’s Specialty Financial division and has more than 25 years of specialty lines experience.

John Rafferty has joined Arch Insurance to head the executive assurance division of the Financial & Professional Liability Group. Rafferty has more than 20 years of executive assurance experience, most recently leading Hartford’s Financial Products division.