A method for removing particulates from internal combustion exhaust gases in a system which includes a first gas conduit which connects with an engine exhaust pipe and which communicates with a trapping chamber containing means for filtering or trapping particulate matter present in the exhaust gas. A second gas conduit connects with said first gas conduit at a location upstream of the said trapping chamber and leads to a regenerating chamber which contains an electrically conductive substrate which carries an oxidation catalyst. A third gas conduit carries the hot gas from the regenerating chamber and connects with said first gas conduit at a location also upstream of said trapping chamber. The electrically conductive substrate material within the regenerating chamber is part of an electrical circuit and is heated by current passing therethrough. Means are provided for injecting a combustible fuel into the regenerating chamber wherein the fuel-exhaust gas mixture is effectively heated and burned therein and the heated gas then passes into the trapping chamber to incinerate and burn off the particulate collected therein. Valve means are provided to selectively direct exhaust gas flow through to the trapping chamber and the regenerating chamber.