The smoke emitted from burning tobacco comprises over 5000 different substances distributed between particles and vapour phase. Due to the high complexity of cigarette smoke it is challenging to find an analytical real time method which can detect organic trace compounds with a wide dynamic range. Photo ionization time of flight mass spectrometry (PI-TOFMS) has proven to be a useful technique to ionize molecules softly and sensitively without fragmentation. With time of flight mass spectrometry a high temporal resolution can be achieved. Thus it is possible to measure puff-resolved changes in smoke composition during the smoking cycle of a cigarette. Resonance enhanced multi photon ionization (REMPI) using a pulsed UV laser is a powerful approach to analyze polycyclic aromatic hydrocarbons (PAH) with high selectivity and sensitivity. Both approaches have been applied in this study on 2R4F Kentucky research reference cigarettes smoked under ISO and Canadian puffing parameters.Until now most published puff-resolved and/or on-line studies have been carried out on smoke exiting the cigarette filter. However, for a better fundamental understanding of the combustion/pyrolysis processes during smoke generation, it is desirable to analyse these complex reactions directly inside the burning coal along the tobacco rod. For this purpose a heated microprobe was constructed which samples directly inside the burning coal. Results obtained from this microprobe linked with REMPI-TOFMS will be presented to demonstrate the puff resolved on-line analysis of semi-volatile (poly)aromatic species (e.g. benzene, toluene, phenol, indol, and phenanthrene) inside the burning coal. The gas mixture reveals different behaviour especially in the coal as compared to mainstream smoke yields at the filter. Furthermore this new sampling technique allows sufficient intra-puff resolution and shows significant differences in the temporal course of yield changes during one puff (particularly pronounced for e.g. indol, trimethylbenzene, and phenanthrene).