Indonesia's President Joko Widodo holds a personal item from Lion Air flight JT 610 at the Tanjung Priok port on October 30, 2018 in Jakarta, Indonesia.

Indonesia's military chief believes that the fuselage of the crashed Lion Air plane has been found, Reuters reported Wednesday.

Hadi Tjahjanto told a local television channel that a search and rescue team had found what appeared to be "a part of the fuselage of JT610," referring to the flight operated by Indonesian budget carrier Lion Air, according to the news agency.

He added that the search team had the location coordinates of the wreckage but was trying to confirm that it was indeed the fuselage.

The aircraft carrying 189 people, including crew, from Jakarta crashed into the sea off the island of Java on Monday, shortly after take-off. Officials have said they are not expecting any survivors.

A transport safety official also said that the team looking for the crashed aircraft heard a ping sound late on Tuesday and divers were set to check the site Wednesday morning, Reuters reported.

The search and rescue team found a 22-meter long object underwater in the area where the plane was said to have crashed, a navy official reportedly told local media.

Transportation and safety officials have been searching for voice and data recorders and other clues to determine the cause of the crash of Lion Air's brand-new Boeing 737 MAX 8 jet. It was the first accident of its kind for the variant of the top-selling plane.

Indonesia deployed divers to search for the plane and is also using "pinger locators" to zero in on the aircraft's cockpit recorders.

Reuters said a witness on a boat at the crash site on Tuesday saw about 60 divers scattered in inflatable boats over slightly choppy waters entering the sea, which is about 35 meters (115 feet) deep. In all, 35 vessels are helping in the search, according to the news agency.

Debris, personal items and human remains have been recovered.

Indonesian transportation officials have said Boeing's 737 MAX 8 planes will not be grounded, despite uncertainty surrounding Monday's crash of Lion Air's brand-new jet.

Lion Air is one of Indonesia's youngest and fastest-growing airlines, flying to dozens of domestic and international destinations. The airline is a major customer of Boeing.

— Reuters and CNBC's Leslie Josephs contributed to this report.

Watch: Brand new Boeing 737 MAX 8 crashes into Java Sea