Four American troops died in two separate roadside bomb attacks in Afghanistan on Monday, the US army announced.
Spokesman Col. Greg Julian said that the two strikes happened in different locations but "not too far from each other." He declined to say where the strikes happened because family members had not yet been contacted.
The four Americans served in eastern Afghanistan under the NATO-led International Security Assistance Force.
The US military said that IED attacks were up 25 percent this year over the same period in 2008. The military predicts IED attacks to spike 50 percent this year after an expected increase in attacks over the summer.