Washington, May 3 (IANS/RIA Novosti) Pakistani military and intelligence officials need to answer many questions to prove that they did not know where Osama bin Laden had been hiding before he was killed in a US raid, a senior US senator said.

The compound where the Al Qaeda leader was killed is located about 100 meters from a Pakistani military academy in the Pakistani city of Abbottabad, which has raised questions on whether the Pakistani military knew where the world’s most wanted terrorist was hiding.

‘There isn’t any question that Pakistani officials, army and intelligence have a lot of questions to answer, given the location of the compound, the length of time he was there and that this facility was apparently built for bin Laden,’ Carl Levin, who heads the US Senate’s Armed Services Committee, told journalists in Washington Monday.

Controversial statements by US and Pakistani officials over the raid make it difficult to assess the contribution of the Pakistani intelligence and military to Osama’s killing.

After US President Barack Obama announced the death of Osama, US intelligence officials told journalists in Washington that the Pakistani authorities had not been informed about the raid.

US Secretary of State Hillary Clinton said later on Monday that a ‘close cooperation’ with Pakistani special services helped the US to ‘achieve our targets’.

The statement came amid media reports that a Pakistani helicopter had been shot down by unknown people close to Osama’s compound in Abbottabad before two US helicopters flew to the site.

A photo of the crashed helicopter was published on the Internet, and witnesses were quoted by media reports as saying that they had seen the wreckage. Obama said no US troops have been killed in the operation.

Some military experts said the US was unlikely to have informed the Pakistani authorities about the planned operation, otherwise Osama would have escaped as a result of information leaks.