Just days after the massive train derailment in India, railway officials say the tracks where the accident occurred were cleared enough to be placed back in service Monday.
"Trains are required to control their speed and proceed slowly for a certain distance," an Indian railways official told Reuters.
Nearly 300 people were killed and more than 1,000 were injured in the three-train accident Friday night.
India's Railway Board wants the country's top investigators to take over the probe into the deadly crash.
It was not immediately clear why the Central Bureau of Investigation is being tapped to conduct the inquiry.
A train was on the wrong track because of an electronic signaling system error, and that error led to India's devastating derailment.
Ashwini Vaishnaw, India's railways minister, said in a television interview Sunday on New Delhi Television, "Who has done it and what is the reason will come out of an investigation."
The trains involved in the derailment Friday collided about 220 kilometers south of Kolkata.
Prime Minister Narendra Modi visited the site Saturday.
Emergency workers had to climb on overturned train cars to rescue some victims, while other rescuers cut through the trains' cars to provide emergency services.
Train crashes are a frequent occurrence in India because of aging railway infrastructure. More than 12 million people ride thousands of trains across the country every day.