Civil society activists protest to condemn the rape and killing of Zainab Ansari, an 8-year-old girl, in Karachi, Pakistan. Picture: Shakil Adil/AP
Civil society activists protest to condemn the rape and killing of Zainab Ansari, an 8-year-old girl, in Karachi, Pakistan. Picture: Shakil Adil/AP
Two people were killed and three others were wounded in clashes between angry Kasur residents and police after protesters enraged over Zainab Ansari's death attacked a police station in the city. Picture: Shakil Adil/AP
Two people were killed and three others were wounded in clashes between angry Kasur residents and police after protesters enraged over Zainab Ansari's death attacked a police station in the city. Picture: Shakil Adil/AP
A Pakistani girl joins others during a memorial for Zainab Ansari, an 8-year-old girl who was kidnapped, raped and killed last week, in Lahore. Picture: K.M. Chaudary/AP
A Pakistani girl joins others during a memorial for Zainab Ansari, an 8-year-old girl who was kidnapped, raped and killed last week, in Lahore. Picture: K.M. Chaudary/AP
People attend a memorial for Zainab Ansari, an 8-year-old girl who was kidnapped, raped and killed last week, in Lahore. Picture: K.M. Chaudary/AP
People attend a memorial for Zainab Ansari, an 8-year-old girl who was kidnapped, raped and killed last week, in Lahore. Picture: K.M. Chaudary/AP
Supporters of the Christian People's Movement attend a memorial for Zainab Ansari, an 8-year-old girl who was kidnapped, raped and killed last week. Picture: Fareed Khan/AP
Supporters of the Christian People's Movement attend a memorial for Zainab Ansari, an 8-year-old girl who was kidnapped, raped and killed last week. Picture: Fareed Khan/AP

Lahore, Pakistan - A Pakistani official says a serial killer may have been behind the rape and murder of a young girl whose killing sparked deadly clashes between protesters and police.

Rana Sanaullah, the home minister for Punjab province, says DNA testing has linked the killing to at least five other cases of child abuse and murder in the city of Kasur. Police have detained eight suspects, including two relatives of the girl.

Read: Two killed in protests after 7-year-old Pakistan girl's rape and murder

Eight-year-old Zainab Ansari went missing last week while heading to a nearby home for religious studies. The discovery of her body, which was found in a garbage bin Tuesday, ignited clashes between residents and police that killed two people and wounded three others.

The residents say the authorities were slow to respond to the girl's disappearance, charges denied by police.

AP