WASHINGTON (AP) — Amtrak says train service between Philadelphia and Washington has been restored after being suspended because of damaged overhead wires.

Spokesman Craig Schulz says passengers should expect delays as crews continue repairing the system and restoring the second track for service.

Rail service had been suspended earlier Wednesday after overhead wires were damaged in northeastern Maryland. The damage meant that Acela Express, Northeast Regional and other services were not operating between the two cities.

Amtrak says the cause remains under investigation.