Federal officials were quick to point responsibility to the al-Shabaab Muslim extremist group associated with al-Qaida, Capital FM News reported.
Vice President Kalonzo Musyoka visited survivors in a hospital Saturday night and told reporters "We urge for calm."
Kenyan military forces are engaged in an anti-terror mission in neighboring Somalia against al-Shabaab and other militias and the country has become a target.
However, the vice president told reporters "we will definitely win the war against terrorism."
National Police spokesman Charles Owino echoed the sentiment at a news conference.
"This is a cowardly act by al-Shabaab elements," he said. "But we will not relent in the war. We will get them and we will continue with the war."