Legal requirements were not fulfilled in the trial, Jamaat-e-Islami chief Qazi Hussain Ahmed said in Islamabad. "Omar Saeed Sheikh was made scapegoat in the case. This act is highly condemnable."
An anti-terrorism court on Monday sentenced to death the British-born terrorist for the abduction and killing of the Mumbai-based Wall Street Journal correspondent.
Three co-accused in the case were given life terms of 25 years.
The chief of the Muttahida Majlis-e-Amal, an alliance of six religious groups, Maulana Shah Ahmed Noorani said the trial should be reopened.
The Jamiat Ulema-e-Islam leader, Abdul Karim Abid, said: "It is not our verdict at all. Sheikh Omar is innocent and the government made him a culprit to appease the United States."
Meanwhile, the United States welcomed the sentence, saying that it was an evidence of Pakistan's commitment to the war against terror.
"Daniel Pearl was brutally executed and Pakistan's court system has now ruled. This is an example of Pakistan showing leadership in the war against terror," White House Press Secretary Ari Fleischer said.
The State Department said it was "gratified" by the verdict.
"This is an important step in bringing to justice the perpetrators of this vicious crime," spokesman Richard Boucher said.
The Daniel Pearl Case: The Complete Coverage
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