Among the large varieties of active galactic nuclei ( AGN ) known , narrow line Seyfert 1 ( NLSy1 ) galaxies are a puzzling class , particularly after the discovery of \gamma -ray emission in a handful of them using observations from the Fermi Gamma-ray Space Telescope .
Here , we report the discovery of a rare large double lobed radio source with its radio core associated with a NLSy1 galaxy SDSS J103024.95+551622.7 at z = 0.435 .
The lobe separation is 116 kpc which is the second largest known projected size among NLSy1 radio sources .
This finding is based on the analysis of 1.4 GHz data from the Faint Images of the Radio Sky at Twenty-centimeters ( FIRST ) archives .
Along with the core and edge-brightened lobes we detected significant ( 30 % ) fraction of clear diffuse emission showing typical back-flow from FR II radio galaxy lobes .
For the source , we estimated a jet power of 3 \times 10 ^ { 44 } erg s ^ { -1 } suggesting that its jet power is similar to that of classical radio galaxies .
Emission from the source is also found to be non-variable both in the optical and mid-infrared bands .
Identification of more such sources may help to reveal new modes of AGN and understand their role in black hole galaxy evolution .