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We present the results of extensive modeling of the spectral energydistributions (SEDs) of the closest blazar (z=0.031) Markarian 421 (Mrk 421)during a giant outburst in February 2010. The source underwent rapid fluxvariations in both X-rays and very high energy (VHE) gamma-rays as it evolvedfrom a low-flux state on 2010 February 13-15 to a high-flux state on 2010February 17. During this period, the source exhibited significant spectralhardening from X-rays to VHE gamma-rays while exhibiting a "harder whenbrighter" behavior in these energy bands. We reproduce the broadband SED usinga time-dependent multi-zone leptonic jet model with radiation feedback. We findthat an injection of the leptonic particle population with a single power-lawenergy distribution at shock fronts followed by energy losses in aninhomogeneous emission region is suitable for explaining the evolution of Mrk421 from low- to high-flux state in February 2010. The spectral states aresuccessfully reproduced by a combination of a few key physical parameters, suchas the maximum $\&$ minimum cutoffs and power-law slope of the electroninjection energies, magnetic field strength, and bulk Lorentz factor of theemission region. The simulated light curves and spectral evolution of Mrk 421during this period imply an almost linear correlation between X-ray flux at1-10 keV energies and VHE gamma-ray flux above 200 GeV, as has been previouslyexhibited by this source. Through this study, a general trend that has emergedfor the role of physical parameters is that, as the flare evolves from a low-to a high-flux state, higher bulk kinetic energy is injected into the systemwith a harder particle population and a lower magnetic field strength.

Time dependent spectral modeling of Markarian 421 during a violent outburst in 2010