Philippine Roman Catholic bishops and priests led by the auxiliary bishop sprinkle holy water Tuesday at the site of the deadly hostage-taking after a mass for peace in Manila. Photo: AFP

The Philippine authorities promised Tuesday a credible probe into the deadly bus hijacking a week ago, but they also said that the preliminary results of the investigation won't be made public.

Justice Secretary Leila De Lima told reporters that she expected a report by mid-September, and anyone found responsible for the deaths of tourists last week could face criminal, civil and administrative penalties.

"This is meant to be a full, thorough, comprehensive and credible investigation," de Lima said at a news conference.

According to a report on ifeng.com, De Lima also said that under the order by Philippine President Benigno Aquino, investigators are not allowed to disclose any preliminary results to the media without government authorization.

The restriction also applies to the investigation conducted by Hong Kong authorities, which means media groups from Hong Kong are barred from any unauthorized disclosure.

Meanwhile, Ricky Carandang, a spokesman for Aquino, said the president has urged the media to show more restraint in covering crisis situations.

Also Tuesday, at the Quirino Grandstand, where the day-long siege played out, a memorial service opened with Buddhist prayers and chants.

China's ambassador to the Philippines, Liu Jianchao, said after the service that a fair and thorough investigation would help relieve the anger and loss of Chinese people.

Agencies- Global Times