A Pakistani judge on Thursday issued an arrest warrant for Makhdoom Shahabuddin, just hours after he was nominated by the president to become the country's next prime minister.
A court witness told AFP that the warrant was issued in connection with the alleged import of an illegal drug in 2010 while Shahabuddin was health minister.
Judge Shafqatullah Khan also issued a warrant for Ali Musa Gilani, son of former prime minister Yousuf Raza Gilani, who was dismissed from office by the Supreme Court on Tuesday for contempt.
Khan said the two men should be arrested and produced before the anti-narcotics court in Rawalpindi, the headquarters of the Pakistani army and twin city of the capital Islamabad.
An investigator from the anti-narcotics force told the court that evidence already given by Shahabuddin and Gilani junior had "not convinced" investigators of their innocence.
"We want them to be arrested so we can investigate them further," he said.