Pearl case defendants plead not guilty

Saeed: The prime suspect in the case

KARACHI, Pakistan (CNN) -- A taxi driver has testified that he saw the murdered U.S. journalist Daniel Pearl get into a car with the man suspected of masterminding his abduction and death.

Ahmed Omar Saeed Sheikh, along with Sheikh Adil, Salman Saquib, and Saquib's brother, Fahad Naseem are charged with murder, harassment of the public, kidnapping & conspiracy to kidnap. If convicted, they could face the death penalty.

The four suspects pleaded not guilty to the charges Monday, although it was not a formal plea. When asked if they agreed with the charges against them, the suspects responded, "No".

In court, taxi driver Nasir Abbas said he drove Pearl to a restaurant January 23 where he saw the journalist and the alleged mastermind of the kidnapping and murder get into a white car. Abbas identified Saeed in the court room.

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Leading up to the trial the prosecution said its case would be based on videotape and circumstantial evidence.

On February 21, the U.S. State Department confirmed Pearl was killed, based on a videotape showing his body, which has not yet been found.

Previously, chief prosecutor Raja Qureshi has said "the entire case will hinge on circumstantial evidence and expert testimony."

The prosecution expects Pearl's widow, Mariane Pearl, to be called as a witness to testify in the trial.

U.S. officials have said they would like to extradite Saeed from Pakistan to stand trial in the United States, but Pakistani officials say the case must first run its course in their nation.

He has been indicted by a federal grand jury in New Jersey, charged with one count of hostage-taking resulting in Pearl's death and one count of conspiracy to commit hostage-taking resulting in Pearl's death.