U.S.-based pharmaceutical giant Pfizer says it has begun paying victims and families affected by a 1996 drug trial that killed and crippled children in northern Nigeria.

Pfizer on Thursday said it made payments of $175,000 to the families of four children who died in the study. The payments were made after relatives provided DNA evidence to show that they were related to the deceased individuals.

The payments are part of the $75 million settlement Pfizer made with the Nigerian government over the trials.

In 1996, the drug company tested the controversial antibiotic Trovan during a meningitis epidemic in the Nigerian state of Kano.

Eleven children died after taking Trovan, which is alleged to have caused deformities such as blindness, deafness, brain damage and paralysis in many others.