Violence killed at least 42 people, including 16 bus passengers caught in a roadside bombing in southern Iraq, after the deadliest day for U.S. troops in precisely six months. The US military announced Tuesday that three American soldiers were killed in a roadside bombing north of Baghdad on Monday, bringing to eight the number of troops who died that day. The last time so many US military personnel were killed in Iraq was Sept. 10, when 10 died. Bloodshed has increased recently, despite what the military said has been a 60 percent drop in attacks across Iraq since June. Last Thursday, two massive bombs killed 68 people in Baghdad's Karradah neighborhood. On March 3, two car bombings killed 24 people in the capital. According to an Associated Press count, at the height of unrest from November 2006 to August 2007, on average approximately 65 Iraqis died each day as a result of violence. As conditions improved, the daily death toll steadily declined. It reached its lowest point in more than two years on January 2008, when on average 20 Iraqis died each day.