Police said they were called to the cemetery after a "disturbance", believed to be a stabbing.
Witnesses reported a huge police presence at Western Cemetery in the Ely area of the Welsh capital.
Around 30 officers were at the scene along with multiple ambulance crews.
Police have rushed to Western Cemetery, Cardiff following a 'disturbance'
One witness described the huge police response.
They said: “[There are] a lot of them in combat helmets and clothing.”
Police outside Western Cemetery in Cardiff this afternoon
South West Police Cardiff tweeted: “Police presence in #Ely after disturbance btwn groups known to one another. Two men non-life threatening injuries #CardiffPoliceIncident.”
They later added: "Armed officers responded only as precautionary measure to #ElyPoliceIncident. Order now restored at the location. Investigation underway."
Three people in total are thought to have been taken to hospital with non-life threatening injuries.
Police at the scene in Cardiff this afternoon
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A Welsh Ambulance Trust spokesperson said: “We were called at approximately 12.45pm to reports of an incident at Western Cemetery, Ely, Cardiff.
“Three paramedics in rapid response cars, two crews in emergency ambulances and members of the Hazardous Area Response Team are at the scene.”
The situation has now been stood down by police.