Police search for Nigeria finance minister's mom, a day after her abduction in oil-rich delta

Police say that they are searching for the mother of Nigeria's finance minister a day after she was kidnapped from her home in the West African nation's oil-rich southern delta.

Nigeria's police spokesman Frank Mba said Monday that the police had launched a "comprehensive investigation" into the abduction of Kamene Okonjo, mother of Nigeria's Finance Minister Ngozi Okonjo-Iweala.

Okonjo-Iweala is a respected economist who was nominated earlier this year to become World Bank chief before losing to U.S. nominee Jim Yong Kim.

Her mother's kidnapping comes as the country has seen a spate of kidnappings and growing sectarian violence.

Experts say kidnappers that once targeted mainly expatriate oil workers have shifted their focus to wealthy Nigerian families in recent years. Nigeria's oil-rich delta is a kidnapping hotspot, but many go unreported.