Amtrak is investigating how an Acela Express train to Philadelphia and Washington left New York's Penn Station without 85 passengers.

The New York Daily News quoted one passenger as saying ticket holders were sent to the wrong platform, but Amtrak spokesman Craig Schulz described the problem only as an apparent miscommunication "between the train crew and the station staff which resulted in the train departing before all passengers could board."

Schulz said some passengers did board Acela train No. 2253, which originated in Boston, before it left New York about 3 p.m. on Saturday.

"An investigation is underway to determine the reason for the breakdown in communication," Amtrak said in a statement. "All affected passengers were accommodated on other trains and Amtrak sincerely apologizes for the inconvenience."

Damien Miano, of Manhattan, told the Daily News that "They literally sent us to the wrong platform, and the conductor took off without any passengers."

"The right hand didn't know what the left hand was doing," Miano said. "It was just so bizarre."

The reported snafu came just days after the railroad reported its trains have been late nearly 30 percent of the time in the last 12 months, considerably worse than the year before.