A little known terror outfit called Tehreek-e-Galba-e-Islam has claimed responsibility for Monday's attack on policemen here and said it was to avenge police firing on Muslims protesting the 2007 blast at the historic Mecca Masjid.

One home guard was killed and a police constable was injured when unidentified gunmen opened fire at a police picket in Falaknuma in the old city Monday.