An internal combustion engine system (20, 20', 20", 20′′′), comprising - an internal combustion engine comprising a first set of one or more cylinders and a second set of one or more cylinders which is separate from the first set, - an exhaust gas recirculation conduit for recirculating exhaust gas from the first and second sets of cylinders (22, 24) to an inlet of the internal combustion engine, - a first EGR valve for controlling flow of exhaust gas from the first set of cylinders to the EGR conduit, and - a fuel injector for injection of fuel into at least one cylinder of the second set of cylinders, characterized in that the system further comprises - a second EGR valve (44, 44') for controlling flow of exhaust gas from the second set of cylinders to the EGR conduit, - a controller configured to control the closing of the second EGR valve (44, 44'), thereby preventing flow of exhaust gas from the second set of cylinders to the EGR conduit, and configured to activate the fuel injector for late post injection of fuel into at least one cylinder of the second set of cylinders when the second EGR valve (44, 44') is closed, so that at least a part of the fuel that exits the second set of cylinders is uncombusted, - a turbine arranged to receive and be driven by exhaust gas which is not recirculated in the EGR conduit, and - an exhaust gas aftertreatment system arranged to receive and treat exhaust gas which is not recirculated in the EGR conduit, the exhaust gas aftertreatment system comprising an oxidation catalyst for combustion of the late post injected fuel or derivates thereof, wherein, for the exhaust gas flowing from the second set of cylinders, the second EGR valve (44, 44') is located upstream of the turbine, wherein the second EGR valve is additionally configured to control flow of exhaust gas from the first set of cylinders to the EGR conduit, wherein the system further comprises an EGR cooler provided in the EGR conduit, wherein the first EGR valve is fluidly connected to the EGR conduit downstream of the EGR cooler. - an internal combustion engine comprising a first set of one or more cylinders and a second set of one or more cylinders which is separate from the first set, - an exhaust gas recirculation conduit for recirculating exhaust gas from the first and second sets of cylinders (22, 24) to an inlet of the internal combustion engine, - a first EGR valve for controlling flow of exhaust gas from the first set of cylinders to the EGR conduit, and - a fuel injector for injection of fuel into at least one cylinder of the second set of cylinders, characterized in that the system further comprises - a second EGR valve (44, 44') for controlling flow of exhaust gas from the second set of cylinders to the EGR conduit, - a controller configured to control the closing of the second EGR valve (44, 44'), thereby preventing flow of exhaust gas from the second set of cylinders to the EGR conduit, and configured to activate the fuel injector for late post injection of fuel into at least one cylinder of the second set of cylinders when the second EGR valve (44, 44') is closed, so that at least a part of the fuel that exits the second set of cylinders is uncombusted, - a turbine arranged to receive and be driven by exhaust gas which is not recirculated in the EGR conduit, and - an exhaust gas aftertreatment system arranged to receive and treat exhaust gas which is not recirculated in the EGR conduit, the exhaust gas aftertreatment system comprising an oxidation catalyst for combustion of the late post injected fuel or derivates thereof, wherein, for the exhaust gas flowing from the second set of cylinders, the second EGR valve (44, 44') is located upstream of the turbine, wherein the second EGR valve is additionally configured to control flow of exhaust gas from the first set of cylinders to the EGR conduit, wherein the system further comprises an EGR cooler provided in the EGR conduit, wherein the first EGR valve is fluidly connected to the EGR conduit downstream of the EGR cooler.