The Russian consul general in Sudan and his wife have sustained knife injuries in an attack in the capital Khartoum, a consulate official said.
The attacker, from the Central African Republic, said he wanted to attack any Westerner to avenge the recent death of his brother in his violence-plagued home country.
"There was no motive other than revenge for the death of [his] brother," Khartoum police said in a statement on Tuesday, Reuters reported.
The victims were taken to a hospital in stable condition and released after a check, said the charge d'affaires of the Russian Embassy in Khartoum, Yury Vidakas.
The embassy ramped up security measures following the attack, limiting staff movements and assigning guards to diplomats, Vidakas said.