By Owais Tohid BBC reporter in Karachi

Pakistan has launched its second Agosta class submarine.

"The new sub marine... will help maintain peace and stability in this volatile region, by deterring our main adversary from any kind of adventurism," a Pakistani navy press release said.

The Saturday launch comes three months after the killing of 11 French technicians in a suicide attack in southern port city of Karachi.

The Agosta 90-B has been designed to operate as an anti-submarine, anti-surface and intelligence gathering [platform]

Pakistani navy statement

The French technicians were in Karachi to help Pakistani naval engineers construct the submarine.

Navy spokesman Commander Roshan Khyal said the highly equipped submarine will be incorporated into the naval fleet after six months of sea trials.

Experts say the Agosta 90-B can stay at sea longer than Pakistan's other submarines.

The third and the last of the three Agosta 90-B submarines is to be built completely in Pakistan.

Controversy

The launching ceremony of the Agosta 90-B was held at the Pakistan naval dockyard in Karachi, where senior Pakistani naval officials and officials from the French embassy were present.

The vessel was manufactured at the naval dockyard of this port city by local shipbuilders with the help of French marine engineers.

The submarine is equipped with four bow torpedo tubes and missiles.

"The Agosta 90-B has been designed to operate as an anti-submarine, anti-surface and intelligence gathering [platform]... and is also capable of diving deeper than 300 meters (1000 feet) with a maximum sprint speed of 20 knots (40 kilometres per hour)," the Pakistani navy said in statement.

The three Agosta class submarines were part of an agreement signed between former premier Benazir Bhutto and the French Government in 1994.

The first sub-marine was constructed in France and went into service in 1999.

The deal ran into controversy when in 1997 the then Prime Minister, Nawaz Sharif, sacked the naval chief, Admiral Mansoor-ul Haq on charges of corruption,

Three naval officials were court-martialled and fined for receiving bribes in the deal.