BAGHDAD, Iraq (CNN) -- Nineteen U.S. troops were killed in Iraq in May, the fewest killed in any month since the war started.



Baghdad saw a lull in violence in May, as a cease fire agreement has so far been maintained.



The second-lowest month for American deaths was in February 2004, when 20 were killed.



May's toll was a significant decrease from April, when 50 were killed -- the highest monthly figure since September.



The U.S. military death toll spiked last year as the U.S. troop escalation, dubbed the "surge," was unfolding. In 2007, there were 104 deaths in April, 126 in May and 101 in June.



Numbers began dropping when the "surge" strategy took hold and Shiite cleric Muqtada al-Sadr suspended the activities of his militia, the Mehdi Army. There were 78 American deaths in July, 2007; 84 in August; 65 in September; 38 in October; 37 in November; 23 in December; 40 in January; 29 in February; and 38 in March.



May's death numbers appeared to support Senate testimony last month from Gen. David Petraeus, the top U.S. commander in Iraq. Petraeus said recent operations in three Iraqi cities have "contributed significantly to the reduction in violence."



The month of June may not bring such optimistic news.



A suicide car bomb struck an Iraqi police checkpoint outside police headquarters in Mosul on Monday, killing nine people, including four police officers, and wounding 46 people, a Mosul police official said.



Eight of the wounded were police officers, the official said.



The incident took place in southern Mosul's Dawasa commercial area at about 7 p.m. the official said.



Mosul is about 260 miles (420 km) north of Baghdad.
How many U.S. troops were killed in Iraq in May? What is "surge" strategy? How many deaths  were there last April? Where were 19 US troops killed? What did a suicide car bomb strike? How many people were killed by the suicide car bomb at an Iraqi police checkpoint on Monday? When were they killeld?
Nineteen U.S. troop escalation, 50 Iraq an Iraqi police checkpoint nine May,
question: How many U.S. troops were killed in Iraq in May?, answer: Nineteen | question: What is "surge" strategy?, answer: U.S. troop escalation, | question: How many deaths  were there last April?, answer: 50 | question: Where were 19 US troops killed?, answer: Iraq | question: What did a suicide car bomb strike?, answer: an Iraqi police checkpoint | question: How many people were killed by the suicide car bomb at an Iraqi police checkpoint on Monday?, answer: nine | question: When were they killeld?, answer: May,