The trial of four Pakistanis accused of trying to kill Pakistani President Pervez Musharraf with a car packed with explosives began on Saturday, with a police officer testifying that the two main suspects had confessed to the crime. The defendants, Mohammad Imran and Mohammad Hanif, admitted their roles in the attempted assassination while being questioned in an unrelated case, police inspector Mohammad Hasan Khaskheli told the Anti-Terrorism court. Imran, Hanif, and two other defendants -- Mohammed Sharib and Mohammad Ashraf -- allegedly belong to the banned group Harkat-ul-Mujahedeen al-Almi. A fifth defendant, Mohammed Wasim Akhter, is a former officer of the Rangers, a Pakistani paramilitary group. All five have pleaded innocent to charges of conspiracy, attempted murder and the use of explosives. On April 26, 2002, Musharraf was traveling from Karachi airport to the center of the southern city when his car drove past a parked vehicle loaded with explosives, police said. The assailants had planned to use them to kill the president, but their remote-control device malfunctioned, the prosecution says. Defence attorney Abdul Waheed Katpar on Saturday challenged Khaskheli's testimony, saying: "This evidence is not admissible under law. He is bringing the confession of accused who were not even arrested in this case at that time." Judge Ale Maqbool Rizvi ruled that the testimony could not be called a confession but that the evidence was admissible. **PHOTO CAPTION*** General Pervez Musharraf's first appearance before the press after staging a military coup against Prime Minister Nawaz Shariff. Rawalpindi, Pakistan 1999