Wielding gas torches and electric cutters, rescuers worked through the night to pull out survivors and the dead from the mangled steel of three trains that derailed one on top of another in a horrific sequence, killing at least 233 people and injuring more than 900 in Odisha's Balasore district, officials and witnessed said Saturday.

Officials in Bhubaneswar said 200 ambulances, 50 buses and 45 mobile health units were working at the accident site, besides 1,200 personnel. The bodies were being taken to the hospitals in all kinds of vehicles, including tractors.

"Death toll rises to 233 in the Balasore Train Accident," Odisha chief secretary PK Jena tweeted.

The train crash, the fourth deadliest in India according to available records, happened near the Bahanaga Baazar station in Balasore district, about 250 km south of Kolkata and 170 km north of Bhubaneswar, around 7 pm on Friday.

Several coaches of the 12864 Bengaluru-Howrah Superfast Express, on the way to Howrah, derailed and fell on adjacent tracks, an official said.

"These derailed coaches collided with the 12841 Shalimar-Chennai Central Coromandel Express and its coaches capsized too," he said.

A goods train was also involved in the accident as some of the coaches of the Coromandel Express, which was heading to Chennai, hit its wagons after getting derailed, he added.

Gas cutters were used to extricate the bodies from under the derailed coaches. Disaster management personnel and firemen were busy at work trying to extricate bodies as dawn broke on this tiny way station on the east coast railway line.

"Some of the scenes at the site were too gory to describe," said a passenger.

Railway tracks were almost destroyed at the spot as mangled coaches lay strewn all over, with some having mounted on another, while a few coaches turned turtle due to the impact.

Pijush Poddar, a resident of Berhampore in West Bengal's Murshidabad district, was travelling to Tamil Nadu in the Coromandel Express to join work there when the accident happened.

"We were jolted and suddenly saw the train bogie turn on one side. Many of us were thrown out of the compartment by the momentum of the derailment. When we managed to crawl out, we found bodies lying all around," he said.

Locals said they heard consecutive loud sounds, following which they rushed to the spot and found the derailed coaches, which were nothing but "a mangled heap of steel".

"The local people really went out on a limb to help us... They not only helped in pulling out people but retrieved our luggage and got us water, " Rupam Banerjee, one of the passengers, told reporters.

One of the coaches “was pushed into the ground " as another from a neighbouring train collapsed on top of it, passengers said.

Work is on to try and extricate that particular bogie and retrieve the dead in it. "This will push up the deth toll significantly," a state disaster relief officer said.

Balasore district hospital looked like a war zone with the injured lying on stretchers in the corridor and rooms bursting at its seams with extra beds propped up.

Harried medical staff were seen trying to bring succour to patients many of whom are from states other than Odisha and had difficulties in communicating.

Policemen, locals have been volunteering to donate blood at this and many hospitals through the night, said officials.

Odisha chief minister Naveen Patnaik declared one-day state mourning on Saturday in the wake of the deadly triple train crash.

State Special Relief Commissioner Satyabrata Sahoo said those injured in the accident were undergoing treatment in different hospitals.

All government and private hospitals have been put on alert in the nearby districts, including the AIIMS at Bhubaneswar.

Railway Minister Ashwini Vaishnaw, who was on the way to the spot, said the Air Force was also called in for assisting the rescue operations.

"Rushing to the site in Odisha. My prayers for the speedy recovery of the injured and condolences to the bereaved families. Rescue teams mobilised from Bhubaneswar and Kolkata. NDRF, State govt. teams and Airforce also mobilised. Will take all hands required for the rescue ops," he tweeted.

More than 2,000 people gathered at the Balasore Medical College and Hospital in the night to help the injured, and many also donated blood.

Chief Secretary Jena thanked the volunteers who donated blood to the accident victims in their hour of need.

"Five hundred units of blood collected overnight here at Balasore. Nine hundred units in stock at present. This will help in treating the accident victims. I'm personally indebted & grateful to all the volunteers who've donated blood for a noble cause," Jena tweeted.

The railways announced an ex-gratia of Rs 10 lakh for the next of kin of the deceased, Rs 2 lakh for those grievously injured and Rs 50,000 for those who got minor injuries.

Prime Minister Narendra Modi too expressed his distress over the accident, and announced an additional ex-gratia of Rs 2 lakh for the next of kin of the deceased and Rs 50,000 for the injured from the PM's National Relief Fund (PMNRF).

"Distressed by the train accident in Odisha. In this hour of grief, my thoughts are with the bereaved families. May the injured recover soon. Spoke to Railway Minister @AshwiniVaishnaw and took stock of the situation. Rescue ops are underway at the site of the mishap and all possible assistance is being given to those affected," he tweeted.

The Odisha government issued helpline 06782-262286. The railway helplines are 033-26382217 (Howrah), 8972073925 (Kharagpur), 8249591559 (Balasore) and 044- 25330952 (Chennai).

Expressing concern over the accident, in which a large number of people from West Bengal were involved, Chief Minister Mamata Banerjee said she was monitoring the situation along with the chief secretary and other officials.

West Bengal Chief Secretary HK Dwivedi said the state was sending a team led by minister Manas Bhunia and MP Dola Sen to the spot.

So far, 18 long-distance trains have been cancelled due to the accident, which happened on the Howrah-Chennai main line in the Kharagpur division of the South Eastern Railway.

Except for the headline, this story has not been edited by The Telegraph Online staff and has been published from a syndicated feed.