AIG's share price has been hit by the on-going criminal investigation the US Justice Department launched last week.

According to reports, the announcement of the investigation into the world's largest insurer wiped 7% of its stock.

Analysts have questioned the reputational risks surrounding the insurer and what long-term damage the investigation will have on the company.

The investigation had been launched to look into a string of off-balance sheet vehicles set up for Pittsburgh bank PNC Financial by AIG, the reports said.