SINGAPORE, Dec. 30 -- The fourth vessel from the Singapore Navy left Singapore on Tuesday evening to join the search and rescue operation for the AirAsia flight QZ8501, which crashed enroute from Surabaya, Indonesia for Singapore on Sunday.

The MV Swift Rescue is a submarine support and rescue vessel equipped with sensors and sonars to detect signals from the plane' s black box.

The Singapore Armed Forces "will do all it can to assist Indonesia in this very difficult time. We offer our deepest sympathies to families of the passengers and crew," Singapore's Defense Minister Ng Eng Hen said in a Facebook post.

The vessel also carries an unmanned submersible that can be remotely operated to search for objects in the sea. There are 35 navy personnel on the mission.

It will take about 24 hours for the vessel to reach its destination and another 20 hours or so if it is to be deployed to the area where the plane debris was found.

The RSS Persistence, a landing ship tank from Singapore with 123 personnel on board, has arrived at the search area about 700 km southeast of Singapore. It carried two Super Puma helicopters from the air force.

The corvette RSS Valour and the frigate RSS Supreme are on their way, too.

Singapore's Air Force had earlier sent two C-130 aircraft to assist in the search. The Transport Ministry's Air Accident Investigation Bureau specialists will depart for the search area on Wednesday morning.