Commercial services of the country's first underwater metro train commenced in Kolkata on Friday with hundreds of passengers erupting into jubilation on their first ride.

A train began its journey from the Howrah Maidan station on the East-West metro corridor of Kolkata at 7 am with loud cheers and claps from commuters, while another started from Esplanade station at the same time. Hundreds of commuters thronged the stations in the early morning to be part of the "first-day first underwater metro" bandwagon.

At Howrah Maidan station, passengers were seen standing in a long queue in the morning to get a ticket, while the authorities greeted them with rose stems at Esplanade station. There was excitement among the passengers while a section of commuters at the Howrah Maidan station started chanting 'Jai Sri Ram' slogan as they boarded the train.

The commercial services began after Prime Minister Narendra Modi had on March 6 inaugurated the Howrah Maidan-Esplanade section of Kolkata Metro's East-West corridor, heralding India's first venture into underwater metro services.

As the train entered the under-river stretch, passengers on board erupted in joy while a section of commuters started raising slogans - "this is Modi ki guarantee" and some enthusiastically rushed to the window to get a glimpse of the illumination of the tunnel wall under the Hooghly river.

A special illumination of the inner wall of the tunnels under the river with blue light has been arranged to give the effects of water around the moving rake. The under-river section of the tunnel is 520 metres long, and a train took around 45 seconds to cross it.

"So far, we get an overwhelming response, and people even came as early as 2.30 am to experience the first underwater metro services in the country," Metro Railway spokesperson Kaushik Mitra said.

The Howrah Maidan-Esplanade section, a groundbreaking addition to the metropolis' transportation network and touted to be the first transportation tunnel under any mighty river in India, has the deepest metro station in the country -- the Howrah Metro station.

According to a statement issued by the Metro Railway, the 4.8-km stretch of East-West Metro from Howrah Maidan to Esplanade has been built at a cost of Rs 4,965 crore.

The Salt Lake Sector V to Sealdah stretch of the corridor has already been commercially operational. The work for the East-West corridor began in 2009 and tunneling under the Hooghly river commenced in 2017.

Of the total 16.6 km of the corridor, 10.8 km is underground, including the tunnel beneath the river.

The project has suffered delays owing to an aquifer burst at Bowbazar in central Kolkata on August 31, 2019, leading to severe ground subsidence, the collapse of several buildings there and two more water leakage incidents at the same site in 2022 during tunnelling and construction work.