The officer was in the company of three others and had responded to a distress call when they came under fire. Police say the officer was shot and injured in the leg as the suspected thugs escaped on foot.
He is recuperating in hospital.
Meanwhile, seven suspected thugs were at the weekend shot dead by police in two separate incidents of crime in the city.
The first incident happened in Mwiki area where three suspects were killed after a chase by police. A pistol was recovered from the three. Four others were yesterdaykilled in Umoja area in a botched robbery and two pistols found on them.
Police say the men had been attacking and robbing locals when they were alerted. This increases to more than 30, the number of suspects killed in the past month alone in the war on crime in the city.
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