India's on-field success at the Commonwealth Games in Melbourne was blighted on Thursday after weightlifters Tejinder Singh and Edwin Raju were reported to have returned positive tests for banned substances.

"The two lifters have been told verbally that they are caught for drug abuse. They have already left the Games Village," highly-placed sources said.

"However, the Indian contingent has not received any official communication in this regard," the source said.

When contacted, sources in the Indian Olympic Association said they were "puzzled and perplexed".

"We are puzzled and perplexed about it. Because after WADA (World Anti-Doping Agency] and SAI (Sports Authority of India) had tested the lifters on March 1. They were cleared to travel on March 8. We are puzzled what happened in the meanwhile," the sources said.

Rumours of a drug scandal were rife after Tejinder pulled out of the men's 85 kg class competition at the last minute on Monday, citing "illness".

Edwin Raju finished fourth in men's 56 kg division competition, in which compatriot Vicky Batta won the silver medal, on March 16.

The organising committee had collected their samples and sent them to Sydney for tests.

John Harnden, chief executive officer for the Games, had earlier said that samples of all medal winners, and some at random, had been taken and sent to Sydney for tests.

"It is a long drawn process adhered to under the rules of WADA and we do not disclose either the positive or negative result of the tests to anyone other than the athlete concerned," Harnden said.

"The tests are being done at the Australian Sports Drug Test Laboratory in Sydney and they will inform the Games Medical Commission, which in turn deal with the athlete concerned," Harnden said.

The scandal broke despite the Indian Weightlifting Federation taking stringent measures to prevent any such incident by subjecting its lifters to a series of dope checks in which top medal prospects like P Shailaja in 75 kg and B Prameelavalli in 63 kg were filtered out and the team reached the Games village without the two girls.

The Commonwealth Games is the Indian lifters' first major tournament after a one-year ban from all international competition following a dope fiasco at the 2004 Athens Olympic Games.

The International Weightlifting Federation slapped the ban after Pratima Kumari and Sanamacha Chanu tested positive for testosterone and diuretic furosemide respectively at Athens, and another lifter, S Sunaina, was caught for a doping offence at the Asian championships in Kazakhstan earlier that year.

Indian lifters had also damaged the country's image at the Manchester Commonwealth Games four years ago when Satheesha Rai and K Madaswamy failed the dope tests.

After the duo were stripped of their medals, India slipped down a rung and finished fourth at the last Games. 

• Commonwealth Games coverage

Earlier in the day, Indian contingent chef-de-mission H J Dora and the manager of the weightlifting team for the Games, Harbhajan Singh [Images], denied Australian media reports that Tejinder had tested positive for drugs.

The Australian newspapers reported this morning, "A cloud has gathered over the Indian weightlifting team, with at least one and perhaps two lifters believed to have returned positive drug tests at the Games."

Indian lifters finished with three gold, five silver and a bronze medal at the ongoing Games.