Officials say two separate suicide bomb attacks Saturday in Afghanistan have killed at least 18 people as U.S. Defense Secretary Chuck Hagel visits the nation.
Authorities say at least nine civilians were killed in an attack at the Defense Ministry in Kabul while Hagel was visiting the capital city. At least 13 people were wounded in the attack by a suicide bomber on a bicycle.
Officials say Hagel was in a safe location and was not harmed.
The Taliban has claimed responsibility for the attack, saying the assault was a warning to the U.S. defense chief.
Elsewhere, authorities say an Afghan police officer and eight civilians, mostly children, were killed in the second explosion in the eastern city of Khost.
Hagel arrived in Afghanistan Friday on his first foreign trip since being confirmed as Pentagon chief by the U.S. Senate last week.
Speaking to reporters as he flew to Kabul, Hagel expressed optimism about the transfer of security responsibility to Afghan forces prior to the departure of U.S.-led coalition forces in 2014.
Last month, Hagel's predecessor, Leon Panetta, said that NATO allies were considering leaving between 8,000 and 12,000 international troops in Afghanistan after 2014. There are currently around 100,000 NATO troops in Afghanistan, including 66,000 U.S. troops.
Hagel said that while in Afghanistan he would meet with U.S. commanders and Afghan President Hamid Karzai.