Rescue and search operations continued through the night on the train line between the small towns of Corato and Andria in southern Italy where two passenger trains collided head-on at high speed on Tuesday.
The death toll from the crash stood at 27 today morning with dozens injured, some were in serious condition.
Three carriages were torn apart by the violence of the impact after the two trains hit each other while travelling down the same stretch of track linking the small towns in the southeastern Puglia region.
It was not clear how many people had been on the trains at the time of the collision.
Rescuers used a crane to lift debris and the smashed carriages to search for bodies trapped under the wreckage.
There was no immediate indication of what had caused one of Italy's worst train disasters in recent years, but the government promised a full and swift investigation.
Italian Prime Minister Matteo Renzi visited the site on Tuesday evening, demanding clarity over the events.
The crash happened at around 11.30 a.m. (0930 GMT) on a hot summer's day.
Both trains comprised of four carriages. The front carriages on each were pulverised as they slammed into one another. Sky Italia TV said one of the drivers had died. According to the official Ansa news agency the other driver was alive but in a serious condition.
The stretch of track is operated by a small, private rail company Ferrotramviaria. Italian media said the European Union had earmarked funds to build a second track along the route but that the work had been delayed.
The last major rail disaster in Italy was in 2009 when a freight train derailed in Viareggio, in the centre of the country, and more than 30 people living close to the tracks died in the subsequent fire.