India on Friday described the recent murder of three Indian students in Canada as "terrible tragedies" and said its high commission in Ottawa has taken up the matter of safety of Indians with the Canadian authorities.

The safety, security and welfare of Indian nationals in Canada remains of utmost importance to us, external affairs ministry spokesperson Randhir Jaiswal said.

New Delhi has demanded a thorough investigation into the killing of the three Indians.

"In the last week or so we have had unfortunate tragedies. Three Indian students have been murdered. We are saddened at these terrible tragedies that have struck our nationals in Canada," Jaiswal said at his weekly media briefing.

"We extend our deepest condolences to the grieving families. Our High Commission and Consulates in Toronto and Vancouver are extending all possible help in the matter," he said.

Jaiswal said the Indian missions in that country are in touch with the local authorities for thorough investigation of the incidents.

India's call for safety of Indians in Canada and demand for thorough investigation into the murders of three students came amid frosty ties between the two countries.

"Issues faced by them, especially Indian students, are raised by our high commission and Consulates with the relevant Canadian authorities on a regular basis," he said.

"We have also issued an advisory for our nationals and Indian students to exercise extreme caution and remain vigilant in view of the deteriorating security environment in Canada as a result of the growing incidence of hate crimes and criminal violence," Jaiswal added.

According to official data, over 400,000 Indian students are studying in Canada.

In October, India-Canada ties nosedived sharply after Canada linked Indian High Commissioner Sanjay Verma and some other diplomats to the murder of Sikh separatist Hardeep Singh Nijjar last year.

India strongly rejected all the allegations made by Ottawa in connection to the case and subsequently recalled the high commissioner. The Canadian government had said the Indian envoy and a few other diplomats were expelled from the country.

New Delhi expelled Canadian Charge d'Affaires Stewart Wheeler and five other diplomats following the allegations by Canada.

Asked about reports in Canadian media about instances of Indian high commission in Ottawa refusing visas to certain individuals, Jaiswal described them as a "disinformation" campaign.

"We have seen the said media report. It is yet another example of Canadian media's disinformation to malign India," he said.

"Granting of Indian visas is our sovereign function and we have the legitimate right to deny visas to those who undermine our territorial integrity," he said.

"The commentary that we see in the Canadian media on this matter is akin to foreign interference in India's sovereign affairs," Jaiswal added.

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