The audacious attack on Sri Lanka's cricket team in Pakistan on Tuesday rocked the South Asian heartland of the sport and prompted an immediate review of arrangements for the 2011 World Cup.
The showpiece tournament is due to be jointly hosted by India, Pakistan, Sri Lanka and Bangladesh, the four cricket-obsessed Test nations that make up the sport's financial nerve centre.
"Quite clearly, this event puts a great question mark over the ability of Pakistan to host cricket World Cup matches," International Cricket Council president David Morgan told the BBC.
"Things will have to change dramatically in Pakistan in my opinion if any of the games are to be staged there," Morgan said.
With international cricket in Pakistan effectively suspended for the foreseeable future, the other three World Cup host nations will be hard pushed to make a convincing case that they can offer sufficient security guarantees.
India, which generates an estimated 70 percent of cricket's worldwide revenues, had its security credentials shredded by the Mumbai attacks last November which coincided with a tour by the England team.
One of the main targets of the attacks, when gunmen killed 165 people, was the Taj Mahal Hotel, where the England players had stayed on arrival.
Sri Lanka is struggling to finish off a long-running conflict with Tamil Tiger rebels while Bangladesh is recovering from a mutiny in the armed forces that turned part of the capital Dhaka into a battleground last week.
Seven Sri Lankan cricketers were injured when gunmen opened fire on their bus as it headed to the Gaddafi stadium in Lahore for the third day's play in the second Test against Pakistan.
Before the Lahore attacks, the ICC and administrators in the four host countries were banking on the fact the World Cup was still two years away.
But the world governing body hardened its stance on Tuesday with ICC chief executive Haroon Lorgat warning there will be "some serious repercussions" for Pakistan in the next 48 hours.
"In the next day or two we will have to make some serious decisions and we will," Lorgat told the Indian news channel Times Now.
"There obviously have been breaches and the security has not been good enough. There will be some serious repercussions from this."
Of the 15 World Cup venues that had been identified, eight are in India, four in Pakistan, two in Sri Lanka and one in Bangladesh.
Bangladesh is to host the opening ceremony on February 19, 2011 while the final will be played in India and the two semi-finals shared by Pakistan and Sri Lanka.
Australia and New Zealand are already on standby if South Asia is unable to organise the tournament.
Popular television cricket commentator Harsha Bhogle said the uncertainty worried him.
"I feel sorry for cricket lovers in Pakistan, but the attacks have shown it is not a place for international matches right now," Bhogle told AFP.
"I can't say what will happen in the future, but I know teams will think twice before coming to play in the region."
The attacks came even after the Pakistan government provided what it said was "fool-proof" and "presidential-style" security to the visiting cricketers.
Sri Lanka had agreed to the tour after India pulled out of a scheduled Test visit to Pakistan earlier this year following worsening relations between the two nations over the Mumbai attacks.
The split tour -- Sri Lanka played a one-day series in Pakistan last month without incident before returning for the Tests -- was organised even as other teams were refusing to visit the troubled nation.
World champions Australia led the boycott call, later joined by England, South Africa and New Zealand, forcing the ICC to shift the Champions Trophy out of Pakistan.
That eight-nation tournament, the second biggest after the World Cup, was due to be held in September last year, but will now take place this October at a venue yet to be decided.
Australia's uncompromising stance also forced their one-day series against Pakistan starting next month to be shifted to the United Arab Emirates.