In this letter we briefly describe the first results of our numerical study on the possibility of magnetic origin of relativistic jets of long duration gamma ray bursters within the collapsar scenario .
We track the collapse of massive rotating stars onto a rotating central black hole using axisymmetric general relativistic magnetohydrodynamic code that utilizes a realistic equation of state of stellar matter , takes into account the cooling associated with emission of neutrinos , and the energy losses due to dissociation of nuclei .
The neutrino heating is not included .
We describe the solution for one particular model where the progenitor star has magnetic field B = 3 \times 10 ^ { 10 } G. The solution exhibits strong explosion driven by the Poynting-dominated jets whose power exceeds 2 \times 10 ^ { 51 } \mbox { erg / s } .
The jets originate mainly from the black hole and they are powered via the Blandford-Znajek mechanism .