Blazars are a subclass of Active Galactic Nuclei (AGNs), consisting a jet of relativistic plasma, streaming at very small angles to the observer's line of sight. The direct view of the jet in blazars provides an opportunity to study the emissions originating very close to the central engine i.e the accreting super-massive black hole. The variability in flux is one of the important tools to study the central engine in AGNs. The shortest variability time scale gives the upper limit of the size of emission region and mass of black hole. The simultaneous correlated multi- wavelength study reveals the information about physical mechanisms behind and geometry of jet. A sample of blazars are regularly monitored using 1.2 m Telescope at Mt. Abu Infrared Observatory, operated by Physical Research Laboratory (PRL). Liquid nitrogen cooled CCD Camera and Photo-polarimeter is used as back-end instruments as per requirement. To study the Multi-waveband response of variability event, simultaneous and publicly available Swift and Fermi data is also used. In the present talk I will discuss some of the important results obtained from blazar monitoring project at MIRO.