The day had already seemed like a mass-transit nightmare, with dual power failures on Metro’s Red Line and storm-related lags on some Maryland commuter lines. But more than 1,500 evening-rush riders on the VRE line undoubtedly had the creepiest commute.

A package was discovered about 6 p.m. Wednesday close to tracks near Manassas Park. Its suspected contents: human remains.

“A body part, not a head,’’ said Mark Roeber, a Virginia Railway Express spokesman. He said he heard that from Manassas Park police.

But police officials from the small city said in a news release that they had not identified the contents of the package. They investigated late into the night, and a medical examiner was on the scene.

VRE said late Wednesday that it expects trains to be operating normally on Thursday.

The police investigation stalled trains on the tracks, snarling a commute for four VRE trains as well as delaying some Amtrak riders.

Matt Guilfoyle, 36, of Bristow said he boarded a VRE train at Union Station at 5:05 p.m. It came to a stop after leaving the station in Burke, but few on the train began to worry.

“The occasional long wait is not unusual,’’ Guilfoyle said. Then operators told passengers that the delay might last as long as two hours.

He began hearing rumors on Twitter about the discovery of human remains. The train eventually made its way to a station in Clifton, where he boarded a bus that took him to his destination in Manassas. He didn’t expect to get to his house until 10:30 p.m. It was a five-hour commute for a 30-mile trip.

Still, Guilfoyle said he was reasonably satisfied with VRE’s handling of the ordeal. Other trains on the commuter line dropped off passengers in Alexandria and Burke.

“Overall it was okay,’’ Guilfoyle said. “VRE could have provided a little more clarity . . . but my assumption was that they didn’t know everything that was going on.”

Janet Weaver of Reston was returning home on Amtrak from a family reunion in Maysville, Ky. After leaving Kentucky at 4:30 a.m., the train was to arrive in Alexandria at 5 p.m.

That didn’t happen. The train had already been running 11 / 2 hours late, she said, before it stopped.

“They wouldn’t tell us anything,” Weaver said. Passengers were informed only that they were stopped because of “police activity.”

Weaver said nearby seat mates began checking news on their smartphones and spreading the news.

“But you know the Internet,” she said. “You can’t believe anything it says.”

Weaver was exhausted when she finally arrived at the Amtrak parking lot about 10 p.m. She hugged her friend, who had waited for hours.

“I don’t even know my name anymore,” she said.