About 50 children were forced to spend the night on a train after it broke down near the Romanian capital.
In a separate incident, a goods train slammed into a stationary goods train, causing major delays to rail traffic in the busy summer season.
The children who were aged 6 to 17 were returning from a summer camp at the Black Sea coast.
The train left the resort of Costinesti Wednesday evening and was headed to the southern city of Craiova.
However, shortly before midnight, it broke down in a rural area east of Bucharest. There were conflicting reports why it got stuck.
Media reported there was a lack of electricity to power the train, while the railway chief suggested a tree had fallen on the line.
The youngsters, who were in two separate groups, and other passengers spent at least eight hours on the unlit train. There were no reports of medical problems.
„They had no water, it was pitch black, no air conditioning, no food, nothing,” one mother told ziare.com. “Luckily, some of them had battery on their phones, but not for the whole night.”
A train took them to Bucharest on Thursday morning.
Chief of the Romanian Railways, CFR, Ovidiu Vizante, was reprimanded for trying to pass the responsibility to staff in the field.
Romanian Prime Minister Florin Citu suggested he should be lose his job over his handling on the situation. “If he worked at the government, he’d be at home by now”, he said on social media.
Asked if the railway company would get water to the youngsters, he brushed off the question saying they’d get water “when they are in Bucharest.”
In another incident, a goods train collided with a another goods train in the eastern town of Fetesti on Wednesday evening. Nobody was hurt. Some carriages overturned and crushed by the impact of the collision.
There were delays up to 11 hours on the line which runs from the capital to Constanta on the Black Sea, Digi 24 reported.
Transport Minister Catalin Drula said the driver had consumed alcohol and had fallen asleep. Transport police have begun an investigation.