Train service on Via Rail is expected to return to normal Tuesday after an engine fire forced hundreds of passengers to evacuate a train bound for Ottawa from Toronto on Sunday.

More than 300 passengers and crew members were evacuated from the train when the engine caught fire in an isolated, swampy area in south Ottawa just after 8 p.m.

The train came to a stop just south of the village of Richmond on a four-kilometre stretch of tracks between McBean Street and Kettles Road, about 20 minutes away from Ottawa's Fallowfield station.

Via Rail is now launching an investigation into the matter. The cause of the fire remains unknown.

"Via at this point in time will be taking a look at everything to find out what caused this fire and those are the types of questions that will come out in the investigation," said Via Rail spokesperson Catherine Kaloutsky.

Many of the 324 passengers had to walk about two kilometres in the dark because buses were unable to get to the train, she said. A few, including the elderly, were escorted by firefighters. Others were transported by Via Rail service trucks that are able to drive on the tracks.

The passengers later boarded buses to shelter themselves from the barrage of bugs in the area, and were driven to the main terminal in downtown Ottawa.

"There were younger children, the elderly, who were just sitting there stranded and without water, so it was a little tough," said Sammy Diamantstein, 15.

Others said staff handled the situation well and acted quickly to get people off the train once the evacuation order was given.

"Everyone was off in a matter of minutes. The volunteer fire rescue were also very helpful and ensured everyone made it out safely," Wes and Claire Gariepy wrote in an email to CTV Ottawa.

Minor injuries

Thirteen passengers were treated for minor injuries, including knee and ankle injuries, as well as bug bites.

Ottawa paramedics say the train's two engineers helped make sure all passengers were safely evacuated before they left the scene.

Both men were treated for minor smoke inhalation. They were transported to hospital where they were listed in stable condition Sunday night.

Waiting for hours

Meanwhile, frustrated family members waited hours for loved ones at the main train terminal on Tremblay Road. Some called CTV Ottawa to say Via Rail hadn't passed on any information about the incident.

Kaloutsky said the last passenger arrived at the train station at 12:04 a.m. on Monday. The train was scheduled to arrive just after 8 p.m.

Travellers who were onboard the train will get a full refund on the one-way portion of their ticket, as well as a credit for a future round-trip.

"We want to acknowledge that there were extenuating circumstances. At the same time, we are very pleased with how the evacuation was handled," Kaloutsky told CTV Ottawa on Monday.

Passengers have until 10:30 p.m. Monday to pick up any belongings left on the train.

Travel disruptions between Ottawa and Montreal

The situation continued to cause headaches for passengers travelling between Ottawa and Montreal on Monday after three trains were replaced by buses.

"The equipment that was on Train 46 would have been doing a cycle today between Ottawa and Montreal and because that equipment is not available, we've replaced that by bus," Kaloutsky said.

Via Rail is offering a 50 per cent travel credit to passengers affected by those changes. The situation is expected to be resolved by Tuesday.

With a report from CTV Ottawa's Maggie Padlewska