But Saurav sought to put up a brave face saying he was not discouraged by NASA's denial of having conducted such an examination.
The 15-year-old student was quizzed by police for two hours at his village residence in Ballia district on his return from Delhi late last night.
Superintendent of Police Santosh Kumar Singh said "prima facie, the certificate issued to Saurav stating his achievement appears suspicious and efforts have been launched to check the veracity of the agency which conducted this test." "It does not even have a stamp of the issuing authority," the SP said adding help of different agencies in the field of education were being sought on the issue.
Police and local intelligence unit officials also took Saurav's statement in writing as also his passport, visa and other important documents, official sources said.
Revenue Minister Ambika Chaudhary told reporters in Lucknow that "preliminary inquiry report submitted by Ballia district magistrate V K malik to the government says the very certificate issued to Saurav by the agency conducting the so-called examination was fake as it does not carry either a stamp or monogram".
It has also been found that no passport was issued to Saurav in the past six months from Ballia, Chaudhary said.
"There is another lacunae in Saurav's claim that he reached London in six hours in a chartered flight to appear in the said examination conducted at Oxford Univeristy," Chaudhary said adding the final report on the matter would be available after a thorough probe.
A team has been sent to Kota in Rajasthan where Saurav was studying when he had applied for the said examination on the basis of an advertisemEnt.
The state government had earlier announced a cash reward of Rs. five lakhs for Saurav for his "feat" but withheld it till the completion of the inquiry.
Meanwhile, a special team headed by Additional District Magistrate Ram Surat Yadav has been constituted by the district magistrate of Ballia to conduct the thorough inquiry into the case.
Meanwhile, Saurav told reporters that he was confident of his success and was not discouraged because of the denIal issued by NASA over the examination.
He said he had gone to Jaipur to take the objective-type examination and after that "I was told I would have to go to London to take an international examination.
According to Ambika Chaudhary, Saurav during the inquiry said he was accompanied by just 25-30 people on board the flight to London.
Strangely, Saurabh claimed to have stayed at the Buckingham Palace in London, he added.