Mumbai: Indian defence and maritime authorities on Monday said the oil flow from the sunken ship Rak Carrier has decreased, compared to a day earlier.

According to a statement by the ministry of defence here, the rate of oil spill has reduced to around 1 tonne per hour, as compared to 1.5-2 tonnes per hour on Sunday.

This has been confirmed by an hour-long aerial recce of the oil spill area in the Arabian Sea off south Mumbai conducted by the Indian Coast Guard on Monday morning. A defence spokesman said the oil slick is visibly thin and can be seen as a broken silvery sheen extending upto two miles from the site where the cargo carrier sank on Thursday afternoon.

However, some oil patches have also been sighted as far as 12 nautical miles from the sunken vessel.

Two coast guard ships, Samudra Prahari and Sankalp, are engaged in pollution response operations and another ship, Amrit Kaur, has also been deployed on Monday.

The ships are supported by an Indian Coast Guard Dornier aircraft, which has been deployed at Daman.

Three coast guard teams, comprising 30 personnel, are assisting the Municipal Corporation of Greater Mumbai, Maharashtra Pollution Control Board and other authorities in identifying and analysing the areas affected by the oil spill.

The ship MT Rak Carrier, laden with 60,000 tonnes of coal and 340 tonnes of fuel and diesel, sank on Thursday afternoon, raising apprehensions of an ecological hazard.

The 30 crewmen aboard -- all Indonesians, Jordanians and Romanians -- were rescued in a coordinated effort by the Indian Navy and Indian Coast Guard. The Panama-flagged ship, owned and managed by M/s. Delta Shipping Marine Services, Qatar, was on a voyage from Lubuk-Tutung in Indonesia to Dahej port in Gujarat, carrying a consignment of coal meant for Adani Enterprises Ltd.

Two top officials of the cargo vessel were on Saturday arrested and later released on bail by a Mumbai court.

The duo -- Jordanian Capt. Arkan Younis, 36, and Romanian chief engineer Eonascho Eon, 54 -- were nabbed under the Indian Penal Code (IPC) Section 336, pertaining to endangering life or personal safety of others.

Mumbai oil spill not worrisome: Natarajan

Environment Minister Jayanthi Natarajan on Monday said there was no cause for concern over the oil spill from cargo vessel Rak Carrier which had sunk off Mumbai coast."According to the coast guard, the oil is leaking at a rate of 1-2 tonnes per hour. I have asked local pollution control board to take samples... so far, there is no cause for concern," Natarajan told reporters here.

She said that the coast guard has sprayed 600 litres of aerosol to disperse the spill and action is being taken to reduce the damage.

“The situation is being reviewed and if any action is required, the ministry will take... but as of now, there is nothing to be concerned (about),” she said.

The ministry has already sought a report on the oil spill.

She said that local fishermen were already given an advisory due to bad weather to stay away from fishing till Aug 16.

The city police on Sunday asked people not to go to beaches to avoid getting affected by the oil spill.