V Muraleedharan made the remarks in Rajya Sabha. (File)

Pakistanis invited to an Iftar hosted by the Indian High Commission in Islamabad were actively dissuaded and physically stopped from attending the event by Pakistani agencies, prompting India to lodge a strong protest with that country, the government informed the Rajya Sabha on Thursday.

In a written reply to a question in Rajya Sabha, Minister of State for External Affairs V Muraleedharan said the High Commission of India in Islamabad organised an Iftar and dinner reception on June 1 in accordance with established practice.

Pakistani guests, who were invited, were "harassed, intimidated, actively dissuaded and physically stopped" from attending the function by Pakistani security forces or agencies, he said.

Many guests from the diplomatic community based in Islamabad were also harassed, he said.

"The Government of India has lodged a strong protest with Pakistan side in the matter. It has been conveyed that such act was in blatant violation of diplomatic norms and civilised behaviour," the minister said.

The government has called upon Pakistan to investigate into the events with all seriousness, and share the results of the investigation, Mr Muraleedharan said.

In response to another question on Indian fishermen having been attacked in some foreign countries while they went for deep sea fishing, he said from time to time, Indian fishermen along with their boats are apprehended by authorities of neighbouring countries for allegedly fishing in their waters.

There have been few reports of Indian fishing boats being attacked by Pakistan authorities, he said.

Most recently, in January, an Indian fishing boat was reportedly fired upon and sunk by the Pakistan Marine Security Agency (PMSA), Muraleedharan said.

Similarly, there have been few instances when some Indian fishermen who were arrested on grounds of fishing in Sri Lankan waters have complained of assault by the Sri Lankan Navy, he said.

"Government attaches highest priority to the safety, security and welfare of Indian fishermen. The matter of apprehension of Indian fishermen and their fishing boats is raised at the highest levels and strong protests are lodged in the countries concerned," he said.