An anti-terrorism court sentenced three Muslim militants to life in prison on Tuesday for attempting to kill President Pervez Musharraf in 2002, a state prosecutor said.
The court found the three men guilty of plotting to kill Musharraf by setting off a car bomb as his convoy passed in the southern Pakistani city of Karachi.
However, the car did not explode because the remote control device used to detonate it malfunctioned, a judge at the Karachi's anti-terrorism court said, according to state prosecutor Naimat Randhawa.
It was not clear whether the men planned to appeal.
The three men were from the outlawed Harkatul Mujahideen Al-Almi militant group, police at the time said.
The group has been accused of other attacks in Karachi, including a 2002 bombing at the U.S. consulate that killed 14 people.
Musharraf, a key U.S. ally in the war on terror, has survived at least three attempts on his life since he seized power in a military coup eight years ago. The 2002 failed car bombing in Karachi was the first.