Robbery susp killed on 3rd rail

A robbery suspect suffered a gruesome fate Saturday night when he fled into a Brooklyn subway tunnel and got zapped by the third rail, cops said.

The unidentified man was found dead about 7:45 p.m. after he made contact with the electrified rail inside the Union St. station on the R-line in Park Slope, cops said.

Details of the robbery were still preliminary, but a transit source said the suspect grabbed a woman's purse in the station and took off along the tracks.

Power was shut off at the station following the incident. Shuttle buses were whisking stranded straphangers to the nearby Atlantic Ave. station.