New Delhi, Dec 3 (IANS): Navy chief Admiral R.K. Dhowan Wednesday expressed concern over the recent attempts by terrorists to hijack a Pakistan Navy ship, and said India will now have to be watchful of Pakistani navy vessels.

At a press conference on the eve of the 43rd Navy Day, the navy chief said terror threat from the sea was a real challenge to be dealt with.

Dhowan also expressed concern over the growing port infrastructure of China in neighbouring countries, but said the presence of the Chinese navy in the Indian Ocean was not a threat as it was for the safety of Chinese merchant fleets.

"It is a very, very serious situation which we have taken serious note of," Dhowan said, responding to a question on the attempted hijack of PNS Zulfiqar.

Asked if the navy takes into account the possibility that there might be a jihadi group on board when it encounters a Pakistani ship, he said: "We are taking that aspect into account."

On a lighter note, he said: "Out at sea, when officers on watch report to the captain that we have a warship from another navy, the captain would tell the officer to wish him good morning because he is in international waters and so are you.

"Well, in this changed environment, we have to rethink. We may not wish him good morning and actually carry out a surveillance and figure out who he is," he said.

According to reports, Al Qaeda militants tried to hijack a Pakistan Navy frigate earlier this month and use it to target US Navy vessels on anti-terrorism patrol in the northwestern Indian Ocean.

Dhowan, however, said this increases the threat perception for the navy.

"Terror threat is a real challenge," he said, adding, "challenges have gone up, there are pirates, floating armouries".

On the port infrastructure built by China in neighbouring countries, Dhowan said it was being monitored closely.

"It is an aspect we are monitoring very, very closely. It has certain implications, and we are keeping an eye on all aspects," he said.

On the presence of Chinese warships and submarines in the Indian Ocean, the navy chief said: "China has been operating in the Indian Ocean as it is their trade route. They have occasionally deployed submarines, it is part of securing their maritime assets."

On a dialogue between the Indian and Chinese navies, he said it will happen at an "appropriate time".

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