India orders 4 more maritime spy planes from Boeing worth $1 billion

The pact has been signed with an aim to bolster the navy as it tries to track submarine movements in the Indian Ocean

India has signed a pact with Boeing Co for purchasing four maritime spy planes at an estimated $1 billion, defence and industry sources said, aiming to bolster the navy as it tries to check China's presence in the Indian Ocean.

India has already deployed eight of these long-range P-8I aircraft to track submarine movements in the Indian Ocean and on Wednesday exercised an option for more planes, a defence ministry source said.

"It has been signed," the source familiar with the matter told Reuters. An industry source confirmed the contract, saying it was a follow-on order signed in New Delhi early on Wednesday.