On the heels of two deadly attacks against U.S. forces in Afghanistan this week, U.S. Defense Secretary Robert Gates is expected to brief reporters at the Pentagon Thursday afternoon.

Gates is expected to address the brazen attack Wednesday by insurgents on the U.S. air base in Bagram, Afghanistan which wounded nine troops and killed one U.S. civilian. A car bomb attack Tuesday killed five U.S. troops and one Canadian soldier in Kabul.

Gates is also expected to address the South Korean government's announcement on the results of the investigation into the sinking of a naval ship in March.  U.S. officials have said the South Korean warship was hit by a torpedo launched by North Korea.  South Korean media reports have said South Korea will blame North Korea for the attack.

Thursday's briefing will be his first since he spoke to reporters more than a month ago with Joint Chiefs of Staff Chairman Adm. Mike Mullen, Secretary of State Hillary Clinton and Secretary of Energy Steven Chu to announce the new Nuclear Posture Review.