Philippine President Benigno Aquino said he is in touch with mainland authorities after receiving what he called an insulting letter from the Hong Kong government.
"We were told in very minute detail what we were supposed to do," Aquino said in Manila. He declined to say who signed the letter. "We are not responding to the official letter from the Hong Kong government which, in my view, is insulting."
The Chief Executive's Office said Donald Tsang Yam-kuen had written to Aquino on August 26 to thank the Philippine government for helping Hong Kong officers handle the aftermath of the botched rescue attempt.
Tsang said he was convinced the investigation by Manila would be independent, comprehensive and professional.
The letter was polite and respectful, his office said.
It added that the investigation report should include what had happened, the negotiations between the authorities and the hostage-taker, and also say why the gunman's demands were not accepted in exchange for the release of the hostages.