(CNN) -- Medical examiners identified a second body recovered from the Delaware River in Philadelphia, Pennsylvania, as a 20-year-old Hungarian who was on a tour boat that collided with a barge, the Coast Guard said Friday evening.

Szabolcs Prem's body was recovered Friday afternoon, Coast Guard spokeswoman Crystal Kneen said. Also Friday, the tour boat was lifted from the river, a National Transportation Safety Board spokesman said.

Officials on Friday morning recovered the first body, which was found near where the collision occurred two days earlier, said Kneen. The Philadelphia medical examiner identified the body as that of Dora Schwendtner, 16, also of Hungary, Kneen said.

Rescuers saved 35 people who were on the tour boat, popularly known as a duck boat, at the time of Wednesday's crash. Police said the collision followed a mechanical problem on the boat.

Federal investigators were scheduled to interview crew members Friday.

The boat had a clean record, said the president of Ride the Ducks, who traveled to Philadelphia from the company's headquarters in Norcross, Georgia.

"I can tell you this boat has been inspected frequently. Twice daily. We've never had a problem with this boat," said Chris Herschend.

The company voluntarily shut down operations at all its locations, which also include Stone Mountain Park, Georgia; Branson, Missouri; and San Francisco, California. "What we hope to learn [is how] to prevent this from ever happening again," Herschend said.

Officials said people reacted quickly after the collision.

"The immediate response was amazing," said Coast Guard Capt. Todd Gaitlin. "The private citizens helped [rescuers] get people out of the water."

Lt. Frank Vanore of the Philadelphia Police Department told reporters Wednesday that the boat had "mechanical trouble" and the engine shut down after a fire on board. While the boat was in the river and waiting for help, it was hit by a barge, he said. The boat overturned and passengers were spilled into the river.

National Transportation Safety Board officials were to interview crew members on Friday, agency spokesman Robert Sumwalt said.

The investigation will include reviews from cameras along the river, training and navigation methods and safety equipment.

"We want to find out what happened and issue safety regulations so that this does not happen again," said Sumwalt, who is vice chairman of the safety board.

Alcohol tests on crew members came back negative, Sumwalt said. Drug tests will take longer to analyze. The 10 investigators will also look at allegations that similar boats have previously overheated or had mechanical problems.

Herschend said the company is investigating and assisting fire and police officials.

"I believe this was an accident," he said.

He said he could not speculate on whether there was a fire on board or how the boat's captain communicated during the incident. But he said he believes the unidentified captain followed all procedures. He was unsure how long the boat was dead in the water before the collision.

Asked by reporters Thursday whether the barge was at fault, Herschend said, "I don't want to speculate. For me it is not to assign blame."

He said the 10-year-old craft had portable flotation devices.

Herschend said the company is checking on whether the captain told people to jump off the boat moments before impact. "It is my expectation for the captain that he followed our emergency procedures to the letter," he said.

"Our first priority is the people on board," Herschend said. "Then we are going to work on making sure this never happens again."

The company, Ride the Ducks, is owned by Herschend Family Entertainment.

The company's website posted this message Thursday: "Our thoughts and prayers are with our Philadelphia tour guests, crew members and their families. We are attending to their needs first. In the interim, we have voluntarily suspended our Ride The Ducks operations nationwide. If you already have a reservation, you can receive a full refund or reschedule for a future date. We will resume operations shortly."

CNN's Jesse Solomon, Sarah Hoye and Cassie Spodak contributed to this report.