  The BL Lac Markarian 501 exhibited two flaring activities in the
very-high-energy (VHE) band in May 2009. The lack of correlation between X-rays
and TeV gamma-rays without increasing in other bands suggested that more than
one emission zone could be involved. Moreover, fast variability in the flaring
state was observed, indicating that the emission zones responsible must have
small sizes. We use a lepto-hadronic model with two-zone emission to explain
the spectral energy distribution during quiescent and these flaring states. In
the proposed scenario, the photopion processes explain the VHE flaring
activities successfully, and variability constraints place the activity in a
zone located near the jet's base or named inner blob, while synchrotron
self-Compton emission describing the X-ray signature during that flaring state
occurs in the zone situated far the central engine or named outer blob.
