Australian spinner Ashton Agar, who is currently with his national team in Pakistan for a historic Test series, was the subject of a death threat on social media, according to a report by The Sydney Morning Herald.

The threat was reportedly received by Agar's partner Madeleine, who was warned on her Instagram account that the cricketer must not travel to Pakistan.

The report cited a statement by Cricket Australia (CA), which said it was aware of the social media post, "the nature and content of which has been investigated by the PCB (Pakistan Cricket Board), CA and combined government security agencies".

“There are extensive security plans in place for this type of social media activity, which, in this case, is not considered a risk. No further comment will be made at this time,” the statement read.

According to The Sydney Morning Herald report, a spokesperson for the Australian cricket team confirmed to the publication that Madeleine had indeed received "death threat" on social media.

But team security had investigated the threat and did not believe it was a credible threat, the report quoted him as saying.

The report further said it was being suggested that the threat was made from a fake Instagram account, potentially from India.

The Australian cricket team flew into Pakistan on Sunday for their first cricket tour in nearly a quarter of a century — and into a high-security bubble that will envelop them throughout their six-week stay.

Pakistan has struggled to attract top cricket sides since a fatal terror attack on the visiting Sri Lanka team's bus in 2009. Australia had stopped touring Pakistan even before that. It had pulled out of a tour five years before the Sri Lankan attack after a suicide blast at a Lahore church.

They last played in Pakistan in 1998, winning the three-Test series 1-0 and blanking the hosts in the three one-day internationals.

Having been forced to play their home games abroad — mostly in the United Arab Emirates — Pakistan appeared to have reassured international cricket authorities last year with both New Zealand and England scheduled to tour.

But the Black Caps hastily departed in September just minutes before their first match was due to start, citing security fears, and England postponed tours by both their men's and women's teams soon after.

The decisions incensed Pakistan cricket authorities, who felt they had done everything possible to ensure safety and security.

They say they are again leaving nothing to chance, with nearly 4,000 police and military personnel guarding the team hotel in Islamabad and the cricket stadium in Rawalpindi.