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We have observed Markarian 501 in Very High Energy (VHE) gamma-ray wavelengthband for 70.6 hours from 15 April to 30 May, 2012 using TACTIC telescope.Detailed analysis of $\sim$66.3 hours of clean data revealed the presence of aTeV $\gamma$-ray signal (686$\pm$77 $\gamma$-ray events) from the sourcedirection with a statistical significance of 8.89$\sigma$ above 850 GeV.Further, a total of 375 $\pm$ 47 $\gamma$-ray like events were detected in 25.2hours of observation from 22 - 27 May, 2012 with a statistical significance of8.05$\sigma$ indicating that the source has possibly switched over to arelatively high gamma-ray emission state. We have derived time-averageddifferential energy spectrum of the state in the energy range 850 GeV - 17.24TeV which fits well with a power law function of the form$dF/dE=f_{0}E^{-\Gamma}$ with $f_{0}= (2.27 \pm 0.38) \times 10 ^{-11} $photons cm$^{-2}$ s$^{-1}$ TeV$^{-1}$ and $\Gamma=2.57 \pm 0.15$. In order toinvestigate the source state, we have also used almost simultaneousmultiwavelength observations viz: high energy data collected by$\it{Fermi}$-LAT, X-ray data collected by $\it{Swift}$-XRT and MAXI, opticaland UV data collected by $\it{Swift}$-UVOT, and radio data collected by OVRO,and reconstructed broad-band Spectral Energy Distribution (SED). The obtainedSED supports leptonic model (homogeneous single zone) for VHE gamma-rayemission involving synchrotron and synchrotron self Compton (SSC) processes.

Multiwavelength study of VHE emission from Markarian 501 using TACTIC observations during April-May, 2012