According to railway officials the work was being carried out between Vikhroli and Matunga Road on track four, on which fast trains coming towards Chhatrapati Shivaji Terminus run. Due to the maintenance works, the track was closed from 7 to 11.30 am.

This led to the bunching of trains on the track, causing an average delay of more than an hour. Commuters from distant suburbs like Karjat and Kasara were worst hit, since trains from these stations usually run on the fast track once they enter city limits.

However, chief public relations officer of CR Mukul Marwah said the work was done as part of a mega block which the railways undertake on holidays. He also claimed trains were delayed only by around 45 minutes.

The fast trains were then diverted along the slow track, which delayed the slow trains as well. Over 25 such services were diverted alongthe slow track. Services on the fast track resumed by late afternoon.

In the afternoon, a technical fault on a local at Vikhroli added to the delay of slow trains. According to railway police control, an empty rake on its way to CST developed some faults in its pentagraph at Vikhroli railway station at 3.15 pm. It blocked the track for more than 25 minutes before being set right. As a result, services were delayed by 15 to 25 minutes even during evening peak hours.