A massive explosion in a Chinese port helped propel insurance firm Allied World to a loss of $51.6 million in the third quarter.

The Switzerland-based firm, which maintains a Bermuda operation, said the explosion in Tianjin in August cost it nearly $30 million in claims.

And Allied World also reported net realised investment losses of $113.6 million.

The $51.6 million loss amounts to 57 cents per share and compares to the net income of $30.9 million, or 31 cents per share, for the same quarter last year.

Allied World president and CEO Scott Carmilani said: “Despite a challenging investment environment and a large event loss, we believe that we are well positioned to create shareholder value.

“We continue to be excited about the attractive platform we have built over the last few years.”

The firm also reported operating income of $51.4 million — 56 cents per share — for the third quarter of 2015, compared to operating income of $606 million (61 cents per share) for the same quarter the previous year.

The firm’s gross premiums written rose by more than $46 million (6.5 per cent) for the third quarter compared to the same period last year.

The global markets insurance segment wrote 100 per cent more business, driven by the inclusion of the acquired Asian operations.

Premiums at the North American insurance segment dropped slightly — 1.4 per cent — led by decreases in various lines of business including healthcare and property.

The firm’s reinsurance segment dropped 9 per cent, driven by the non-renewal of several casualty and property treaties.