NEW DELHI, January 22 - RAPSI. The Pakistani National Accountability Bureau has suspended its investigation in the corruption case pending against Prime Minister Raja Pervaiz Ashraf, the IANS news agency reported on Tuesday.

Earlier, the Pakistani Supreme Court ordered Ashraf's arrest.

The investigation has been suspended due to the death of Kamran Faisal, one of the bureau officers probing the case. On Friday, Faisal was found hanged in a hotel room in Islamabad, where he lived with his colleagues. He is reported to have committed suicide. Bureau Chairman Fasih Bukhari said the investigation into the Ashraf case will resume only after the inquiry into Faisal's death is completed, the IANS reported.

The Supreme Court ordered the prime minister's arrest on January 15 over allegations of corruption. The decision was made at a hearing on corruption in energy projects. However, Bukhari said there was insufficient cause to enforce the court ruling.

The arrest was ordered as part of the investigation into the case against nine firms that had previously received advance payments of $225 million from the Cabinet of

Ministers for permission to construct power plants in the country.

However, only several companies completed the construction. The work was largely delayed, and the plants were found to produce insufficient energy volumes. The National Assembly elected Ashraf to head the government in June 2012. He earlier served as the country's water resources and energy minister.

Former Prime Minister Yousuf Raza Gilani was forced out of office after the court convicted him of contempt.

The contempt case was opened in April after Gilani refused to correspond with the Swiss authorities and reopen money laundering cases against President Asif Ali Zardari and other top officials, which were closed in 2007.