A former radio colleague says Khalif has substantial blood loss and is being treated at a local hospital. The colleague spoke on condition of anonymity for safety concerns.
There is no immediate claim of responsibility.
Somalia is one of the world's most dangerous countries for journalists. The Committee to Protect Journalists says 59 have been killed since 1992, soon after civil war erupted in the Horn of Africa nation.
Somali journalists frequently receive threats but police rarely investigate them or adequately protect reporters.
(With inputs from agencies.)