The railway medical officials in their preliminary test did not find any evidence of taking alcohol by the three railway staff, Bangladesh Railway (BR) sources said.

The BR authorities, however, temporarily suspended the driver (locomotive master--LM) Abdul Khaleque, assistant locomotive master (ALM) Chan Miah, and senior sub assistant engineer (SSAE) Zakaria, for not stopping the train at the scheduled station.

The members of probe committee also interrogated two persons from whom the three train staff bought tea at Bhairab railway station on Sunday morning before they were numbed.

"I found something wrong with me when the train was on the way to Narsingdi station and I do not know what happened until 4:00pm Sunday," SSAE Zakaria told the probe body.

The taste of the tea was not normal, he added.

"It is clear that the tea they took was mixed with drugs and the doctors who examined them said no evidence of taking alcoholic beverages was found," said Sarder Sahadat Hossain, divisional transportation officer, Dhaka, and chief of the four-member probe body.

"They were, however, suspended for not stopping the train at the scheduled station," Sahadat Hossain said, adding that the probe committee report will be published in a couple of days.

The probe body is likely to recommend not allowing train drivers to have any meal or anything from outside while on duty or driving a train, said probe body sources.

The three suspended railway staff were found 'benumbed' and 'nearly unconscious' inside the engine room of Dhaka-bound Mahanagar Express after Kubbat Ali, a guard working in the train, managed to stop the train from the last compartment by pulling emergency brake.

After a break at Bhirab station, the train started moving and continued for about half-an-hour.

As the train did not stop at scheduled Ghorashal flag station at 5:00am and went on running fast, the passengers scheduled to get off at Ghorashal started shouting and the passengers got panicked at the unusual situation.

Guard Kubbat tried to stop the train through an emergency measure. After his preliminary efforts failed, he informed high officials in Dhaka about the incident over cellphone. Soon the nearby station on the way to Dhaka was directed to arrange emergency measures to stop the train and red signals were hoisted at different stations on the line.

Later, as the guard managed to stop the train 30 metres from the Narsingdi railway station, the LM, ALM and SSAE were found lying nearly unconscious. After treatment at a railway medical hospital in Dhaka, they were released on Sunday evening.

The train reached Kamalapur railway station at 7:30am, being driven by two railway drivers who were travelling on the same train as passengers.

The train with seat capacity for 500 passengers left Chittagong railway station at 10:30 on Saturday night with about 700 passengers on board. As usual the train driver was changed at Akhaura station. The train halted for a while at Bhairab at 3:30am when the LM, ALM and SSAE had tea in the engine room.

Railway sources said most of the 1750 locomotive masters (train drivers) and assistance locomotive masters under Bangladesh Railway lacks adequate training while they are poorly paid.

With a minimum qualification of Higher Secondary Examination from the science group, a person joins as an ALM and undergoes a two-year basic training on train driving.

On the basis of experience, he becomes an LM. In the first phase, an LM runs a cargo wagon and then he sits on the driving seat of a local train.

It takes around 12-15 years experience to become the driver of a passenger mail train or express train.

The drivers do overtime as they get extra allowances for running over 100 kilometres in a day, which is counted as 'extra mileage'. The drivers often run trains for 150-200 kilometres on a working day.

After a long journey a driver is supposed to take rest for at least eight hours but in most cases a driver sits again on the driving seat within four hours of a long journey, said a high official of Bangladesh Railway.

Running trains by over-worked drivers makes especially the passenger trains vulnerable to accidents, railway sources said.

The engine room is supposed to remain under continuous supervision by a supervisor.

The Dhaka-bound Mahanagar Express crossed a long way violating red signals as the master and assistant master were almost unconscious and the engine would have been stopped without much delay had there been adequate supervision. But the engine remained operative until a train guard could stop it by emergency measures.

It shows that the engine was not under close supervision by an engin e supervisor, the railway official said, adding that the train could have met a fatal disaster if there were a train from the opposite direction or a waiting train on the line at any station it crossed.

Yousuf Ali Mridha, General Manager of Bangladesh Railway Dhaka Division, however, said running train engines are always kept under supervision.