Competition watchdog CCI on Thursday ordered a probe into the possible cartelisation by onion traders that might have led to the spike in the prices of the essential commodity. Sources said, the Director General Investigations of the CCI will submit the report on probe within 45 days. The CCI has taken the suo moto action after making an economic analysis of demand and supply of the product, studying media reports and data from the mandis. Today, retail prices of onion rose by five to 10 rupees per kg to 55 to 60 rupees in metros.Meanwhile, Pakistan on Thursday stopped 300 trucks of onion bound for India at the Wagah land border, saying exports had to be curbed to control rising prices within the country. Reacting to the decision, India said the issue has been taken up with the concerned authorities in Islamabad. Commerce and Industry Minister Anand Sharma said in New Delhi that it is shocking and unfortunate that Pakistan has banned onion exports to India via land route.Asked whether Pakistan's action was in retaliation to India restricting cotton exports, Mr Sharma said New Delhi's decision was not aimed at Pakistan. The government has put a ceiling of 55 lakh bales on cotton exports for the current season. However, a large quantity of onions from Pakistan will be reaching Mumbai via the sea route.