At least 23 people have been injured after two passenger trains heading to famous 15th century ruins in Peru's Cusco region collided on Tuesday. Many of the people hurt in the crash are reported to be foreign tourists.

A Peru Rail train collided with the rear of an Inca Rail train several dozen kilometers from the world-famous tourist attraction near the town of Ollantaytambo on Tuesday morning at around 9am.

The photos of the incident show the windows of a carriage shattered and its metal frame damaged from the impact.

Machu Picchu municipal authorities have confirmed that five people were badly injured in the incident, three of whom were transferred to a hospital in Urubamba Province, while the others were taken to the city of Cusco, the historic capital of the Inca Empire.

The number of injured, initially estimated at 13, then rose to 23, according to Ollantaytambo police spokesman Edson Quispe. Many among them are foreign travelers.

While police have launched an investigation into the incident, there have been reports that the collision was caused by a group of protesters who were refusing to leave the tracks.

#FOTOS: Choque de trenes se registró en la vía de Ollantaytambo a Machu Picchu https://t.co/ZlXD458NnMpic.twitter.com/87gNSxWRC9 — Agencia Andina (@Agencia_Andina) July 31, 2018

A witness told state-run Andina news agency that the Inca Rail train was stranded for nearly an hour as police worked to remove a group of local demonstrators.

"We stopped for an hour, then the protest was cleared, the train continued its route, and five minutes later we felt a strong impact on the back. It was a Peru Rail train that hit us," Valeria Lozana said.

A group of around 30 Peruvian tourists who were unable to buy train tickets to Machu Picchu had blocked the tracks, police stated after the incident. According to locals, the protesters were angry after the train didn't stop to pick them up at the 82km mark, where it normally stops. This time, the driver decided to continue past after seeing how many people wanted to climb on board.

Despite speculation that the delay caused by the protest might have led to the collision with the incoming train, Machu Picchu authorities dismissed this in a statement.