Kalaba, who was appointed in 2014, wrote a scathing message on social media on Tuesday, lashing out at the state of the ruling Patriotic Front party.
Military, intelligence, civilian experts from Namibia, Angola, Zambia, South Africa sent to assist the Lesotho Defense Force
Police say tourists were trying to take picture with stray elephant
6 policemen injured while trying to stop witch-hunt in northwestern Zambia
3 cholera quarantine centers have been formed where victims are being treated
Buying 42 fire engines at $1M apiece is unneeded, and deal was mired in corruption, claims opposition
48 injured, death toll likely to rise, police say
Children from Democratic Republic of Congo aged 2 to 14 were being smuggled to Malawi when they were rescued, say officials
Zambia confirms highest single entry of refugees from Democratic Republic of Congo
"The action to stop a church meeting is regrettable," Amos Chanda, spokesman for President Edgar Lungu, told reporters.
Copper mining giant's standoff over new electricity tariffs threatens thousands of jobs
United Party for National Development vice president Geoffrey Mwamba was acquitted of assault and damage to property
Commonwealth to mediate talks between Edgar Lungu, Hakainde Hichilema, Secretary-General says
5 UPND supporters were arrested following disputed general election of Aug.11, 2016
Edgar Lungu expels ruling party members for insubordination, including one potential challenger for his seat
Lungu last week gave police increased powers of arrest and detention, alleging that opposition parties were behind a string of arson attacks intended "to create terror and panic".
Move by Edgar Lungu follows series of arson attacks, including one Tuesday on a major bank in the capital
Officials say arson sabotage may trigger state of emergency, while opposition suspects government power play
Arrest came after they held news conference to protest continued incarceration of party leader Hakainde Hichilema
IMF official Tsikata says Zambia needs to meet conditions such as improving the fiscal performance
Southern Province tribal chiefs cancel 14 ceremonies to mourn incarceration of opposition party leader Hakainde Hichilema