The Odakyu Electric Railway Co. said Tuesday it has punished two executives and 19 employees for allowing 10 newly hired clerical workers to drive trains on three of its lines in the Kanto region.

The clerical workers, with the help of licensed motormen, drove trains on 19 occasions during the 12 months leading up to Aug. 31 on the Odawara, Tama and Enoshima lines, the company said. None of them are licensed engineers.

Passengers were on board during seven of the cases, including the Odawara Line's popular Romance Car express on Aug. 31, which had 200 passengers on board.

On Aug. 30, a new 23-year-old hire drove a train 40 km during a 45-minute period with as many as 550 passengers on board.

The cases came to light after an anonymous caller -- apparently a passenger -- alerted the railway firm, which prompted the company to hold a news conference Sept. 3.

The 10 new workers were also reprimanded.

The motormen who were supervising the trainees said they had them drive to make them "understand the toughness and importance" of driving operations, the company said, explaining that licensed drivers were watching and helping the trainees by supporting their hands in each case.

The Land, Infrastructure and Transport Ministry issued a warning to the company Tuesday that it take measures to prevent similar incidents by the end of January.