Federal police commissioner Zeynu Jemal said Simegnew was shot in the right side of his head, and a gun was later found nearby.
He said the gun belonging to RPS, a security company was was found abandoned in the grass by the roadside.
The first gun shot took place at 3 am on Friday, where unidentified gun men attacked Baddiers bar located in Arua town, along post office road.
Ministers in the outgoing government of now ex-president Joseph Kabila awarded themselves "golden-handshake" benefits in two decrees which were passed on November 24, that safeguarded lifetime cash payments.
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