A store clerk who immigrated from Egypt was shot and killed early today during a stickup at a convenience store under the Girard Avenue station of the Market-Frankford El, police said.

Police initially said Mustafa Shaker, 50, might have been shot because he did not understand the demands of the two robbers who entered the Trax Foods store and did not move fast enough for them.

A review of surveillance video, however, indicated Shakur, who spoke English, clearly understood a robbery was under way, sources said.

What exactly happened next has not been spelled out yet, but one of the robbers shot the clerk in the face about 2:45 a.m. police said.

Shaker, a naturalized U.S. citizen and father of two teenagers who also drove a cab, was pronounced dead at the scene at 2:54 a.m.

Police hope the surveillance videos from the store will help them in the hunt for the killers.