As the city police does not have the expertise to defuse the shell, stored at an isolated location in the Mumbai Port Trust premises after it was found off Cross Islands on Thursday, Naval Armament Depot has been informed to dismantle the 21 inches tall and seven inches wide metal case.
"Labourers of Jaisu Shipping Company were operating a dredger near Cross Islands when they stumbled upon the shell after their boat suddenly stopped functioning. When they checked, they saw the large cylinder-shaped metal that was obstructing the dredger.
They alerted the port authorities who in turn alerted us," said Pandurang Dhoke, senior inspector at Yellow Gate police station.
Sources said the Bomb Detection and Disposal Squad (BDDS) tried to defuse it after dogs sniffed presence of explosive material but later realised it did not have necessary expertise to dismantle such a shell and decided to call in Navy's bomb disposal squad.
"It appears to be of World War II period. Naval Armament Depot has been informed about it in writing. The depot has its own bomb disposal squad that will defuse the shell in a few days," Dhoke said.
Deputy Police Commissioner Tanaji Gadge has visited the site to ensure the explosive was safely kept.