Three American soldiers were killed in a vehicle accident in southern Iraq on Wednesday, the US military said in a statement. The statement gave no further details of the circumstances of the accident but said it was under investigation. The latest deaths take to 4,216 the number of members of the US military who have died in Iraq since the 2003 invasion, according to a foreign news agency tally based on the independent website www.icasualties.org. US military losses saw a slight rise last month, with 17 troops killed compared with 13 in October and 25 in September, according to the website.