Nigeria:

After Babangida survived an abortive coup, he pushed back the promised return to democracy to 1992. Free and fair elections were finally held on 12 June 1993, with a presidential victory for Moshood Kashimawo Olawale Abiola. Babangida annulled the elections, leading to mass civilian violent protests which effectively shut down the country for weeks. Babangida finally kept his promise to relinquish office to a civilian-run government, but not before appointing Ernest Shonekan as head of the interim government. Babangida's regime has been considered the most corrupt, and responsible for creating a culture of corruption in Nigeria.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". Babangida's reaction to the election results caused violent protests for how long?
weeks