Two high speed trains have crashed south of Madrid on Wednesday morning injuring numerous people and suspending the high speed rail line local authorities have said.

According to rail operator ADIF the collision happened at about 8.54am near Los Yebenes and Urda in Toledo province on the Madrid Andalusia high speed line.

It involved a Renfe AVE train heading from Madrid to Seville and a private Iryo service.

ADIF confirmed it was a rear end collision that caused two Iryo carriages to derail and fall down an embankment. Footage from the scene shows a derailed carriage on an elevated section with twisted metal and wreckage scattered below.

The Renfe train involved was AVE 2080 that departed Madrid Puerta de Atocha at 8am for Seville Santa Justa with 397 passengers on board. The Iryo train had about 146 passengers.

Spanish emergency services deployed all resources including firefighters from Alcazar de San Juan and Orgaz, Civil Protection teams, three medical helicopters and two mobile intensive care units.

Mayor of Urda Manuel Galan told TVE that emergency services asked the town to prepare a sports hall to accommodate passengers and the injured. Mayor of Los Yebenes Jesus Perez said the accident appeared serious.

Regional authorities said the death toll has risen sharply. Early reports confirmed at least 10 dead but local media including El Espanol and Castilla La Mancha emergency services later reported at least 39 to 46 dead and up to 179 injured, with officials warning the number may still rise.

The Castilla La Mancha government raised its territorial emergency plan known as Platecam to level 2 and requested support from the Military Emergencies Unit. Regional president Emiliano Garcia Page said he was heading to the crash site.

Initial reports point to a signalling fault. According to El Pais citing government sources, the LZB train control system failed on Wednesday morning causing about eight trains to halt in the area. The system then switched to manual mode and an operator at Atocha control centre may have mistakenly authorized the Renfe train to proceed while the Iryo train was blocking the track.

A survivor told RTVE that passengers escaped by breaking windows after the violent impact. He said with the violent jolting we started holding on to our seats and managed to get out by breaking windows.

Prime Minister Pedro Sanchez said he was shocked by the serious accident in Toledo and remains in constant contact with the transport minister and the Castilla La Mancha president. He said emergency services are working on the ground to assist those affected. The opposition Peoples Party cancelled all campaign events as the country prepares for general election on November 29.

This is the second major high speed crash on the same corridor in ten months after the Adamuz crash in January which killed 45 people and shook confidence in Spain extensive high speed network.