SEPTA has suspended commuter rail service south of Marcus Hook, Pennsylvania, because of a tractor-trailer accident south of Claymont.The truck swerved off Interstate 495 about six o’clock this morning. It ran through a chain link fence, crossed a grassy strip and a dirt service road, and came to rest, still upright, across three of four sets of railroad tracks.

Those tracks are used by Amtrak’s Northeast Corridor trains, SEPTA commuter trains, and Norfolk Southern freight trains.

Amtrak trains are making their way slowly past the site, but SEPTA has suspended service on its R-2 commuter line between Marcus Hook and Newark, Delaware. SEPTA trains are running from Marcus Hook north to Philadelphia.

Delays can be expected for a while on Amtrak trains between New York and Wilmington.

Traffic is slowing slightly on northbound Interstate 495 in the Edgemoor area of Delaware.

There is no word yet about any injuries or what caused the tractor-trailer to swerve off I-495.