Islamabad, Apr 17 (IANS): Authorities probing the Rs.7 billion scam of illegal sale of ephedrine, a controlled substance used in medicines, have sought a complete record of visitors to Prime Minister Yousuf Raza Gilani's house since 2009, Dawn reported Tuesday.

The Anti-Narcotics Force (ANF) has expanded the scope of its investigations to the Prime Minister's House, the daily said.

On April 9, the government removed two ANF officials who were investigating the scam of illegal sale of ephedrine. Media reports have accused the prime minister's son, Ali Musa Gilani, of involvement in the scam.

The ANF wrote a letter to the chief security officer at the Prime Minister's Secretariat, asking him to provide complete record of visitors to the PM's House.

ANF Joint Director Lt Col Syed Touqir Abbas Zaidi has referred to a case registered at the ANF police station, Rawalpindi, and asked the chief security officer "to provide PM's House entry record from January 2009 to date".

The ANF official has stated that the "information is required in official capacity" under various provisions of Control of Narcotics Act, 1997.

A source close to Gilani told Dawn that the prime minister was upset over the move and was likely to seek "legal measures" against the officials for writing the letter.

An official in the Ministry of Narcotics Control said that the ANF sought the record of visitors as it had learnt that some of the suspects in the ephedrine import scam had been frequently visiting the PM's House.

The scam came to light when the ANF informed a three-judge bench of the Supreme Court that the ephedrine quota worth Rs.7 billion was given to two Multan-based companies under pressure of an influential person, Dawn said.