A 85-year old Dinah Tindimutina is among the four people who died in a road accident at Kyakatwire Town Council in Kyenjojo district on Sunday.
The accident also claimed three of her grandchildren, Denis Muhangi and Caroline Kamusiime.
Police is yet to identify the other victim.
Tindimutuna with her grandchildren were riding on a Bajaj Boxer Motorcycle registration number UET 738Q when it was run over by an Isuzu Elf truck registration number UBD 474F.
The boda boda rider Erias Tumuhereza also died in the same accident.
According to Rwenzori Region Police spokeswoman, Lydia Tumushabe, Bodies of victims are are Kyenjojo Hospital mortuary for postmortem.
Preliminary cause of accident, she said was due to speeding by the truck driver who is still at large.