The demonstrations were spurred by the deaths of two police officers in separate weekend attacks in a Juba suburb, the Sudan Tribune reported Monday.
Gunmen on a motorcycle stormed the residences of the officers Saturday and opened fire, police spokesman James Mande said.
Relatives of the dead officers started the demonstrations, which were joined by other residents complaining of declining security, Mande said, adding that patrols in the area had been boosted and "the situation is calm."
Less than a week ago two brothers were killed in another Juba suburb, prompting demonstrators to carry the bodies of the dead men to the state assembly in a call for greater security.
Police say suspects in those deaths have been arrested.
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