Police are scrambling to identify and arrest the two gunmen who ambushed a North Philadelphia store clerk overnight and shot him dead when he didn't comply quickly enough with their robbery demand.

The victim, a man in his 50s of 60s whose name hasn't been released, apparently spoke Spanish and had trouble understanding his attackers' order, police said. The 2:45 a.m. incident occurred inside the Trax Foods store on Front Street near Girard, underneath the Girard Avenue station of the Market-Frankford El. The victim, shot in the face, died on the scene just before 3 a.m., police spokeswoman Officer Christine O'Brien said. The suspects are described as in their early 20s; they were wearing dark hoodies. One wore a baseball cap with a white emblem.

Tipsters can call homicide detectives at (215) 686-3334.