Naval ships, Coast Guard vessels and the marine police have been put on high alert, Captain M Nambiar, the Indian Navy's spokesman in Mumbai told Rediff.com
Nambiar did not divulge the number of personnel or ships deployed, but confirmed that this is the most enhanced, strict security blanket imposed on the waters around Mumbai.
Guarding the Mumbai coastline, sources said earlier, has been given the most precedence since intelligence alerts hint at likely threats from the sea.
Indian Navy and Coast Guard ships will be assisted by the USS Peleliu, an assault ship with helicopters on board.
Over 5,000 security personnel will protect President Barack Obama on land.
Of these, 2,000 security personnel will be posted at the Taj Mahal and Maurya Sheraton hotels where he will stay in Mumbai and New Delhi.
The first and second rungs of the security cordon around Obama will be formed by the US Secret Service, which protects the American president and his family, and other American security personnel.
The other rungs will be manned by the police in the respective cities and National Security Guard commandos.
All areas around the Taj Mahal hotel, which was attacked by Pakistani terrorists during the November 26, 2008 attacks, have been santised. No pedestrian or vehicular movement around the Taj will be permitted till Obama leaves the hotel on Sunday afternoon.
The Mumbai police have also banned bursting crackers in all areas where the president will visit.
The police have advised residents in Colaba and other areas of South Mumbai not to venture out when Obama's convoy is on the road.
The Union home ministry has issed a security alert ahead of the Obama visit, which will stay in place until the president leaves the country.
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