"A policeman with Afghan National Police (ANP) was martyred and 17 civilians were injured when a mine planted on a donkey was detonated by a remote control device at about 11:00 a.m. (local time) Tuesday in Ganj bazaar area of Ghormach district," the ministry said in a statement.
The ANP has shifted all injured people to a district hospital. It said an investigation has been initiated.
This is the second blast in the insurgency-hit country since Tuesday morning.
Five civilians, including a woman, were wounded earlier Tuesday morning when a magnetic mine attached to their vehicle went off in Qara Bagh district, some 40 km north of capital Kabul, the Kabul police said in a separate statement.
No group has claimed responsibility for the incidents so far.
Tuesday's attacks happened amid the government's preparations to open the traditional Loya Jirga, or grand assembly of tribal elders, lawmakers and government functionaries on Wednesday to discuss the proposed U.S.-Afghan strategic partnership amid Taliban threats.
According to local authorities in northern Afghanistan, at least two people including an Afghan police force were killed and 16 others injured in northern Faryab province early Tuesday.