Philippine police have admitted they did not have the skills, equipment or training to handle Monday's bus siege, in which eight Hong Kong tourists were killed after being taken hostage.
The force said talks with the gunman had been handled poorly, and relations with the media had broken down.
Security experts, survivors and Chinese officials have all criticised the Philippine authorities.
The hostage drama came to an end when police marksmen killed the gunman.
He was identified as 55-year-old Rolando Mendoza, a former policeman who had seized the bus in a desperate bid to get his job back.
In a statement, police spokesman Senior Superintendent Agrimero Cruz listed a number of shortcomings in the police's handling of the situation.
Among them were "inadequate capability, skills, equipment and planning of the assault team" and "inadequate training and competence of assault team leader".
He also said another problem was "non-compliance to media relations procedures in hostage situations".
Police believe the hostage-taker was monitoring TV coverage from inside the bus, which contributed to his agitation as the crisis came to a head.
He was also able to conduct an interview with a local radio station during the siege, and warned the police that he would kill the hostages if they did not pull back.
In an interview with the Philippine Inquirer, Interior Secretary Jesse Robredo admitted that mistakes had been made.
"We recognise that we lack equipment; we could have been better trained, better equipped and there should have been better response," he told the newspaper.
Buddhist monks led prayers for the victims in Manila on Tuesday, while angry demonstrators converged on the Philippine consulate in Hong Kong.
The Philippines has promised a thorough investigation and is sending a delegation to Hong Kong to explain what happened.
Of 25 people initially taken hostage, nine were freed after initial negotiations. The UK Foreign Office said two of them were British nationals.
The Philippine driver then fled the bus, leaving 15 people on board with the gunman until the end of the siege.
Unconfirmed reports say at least one of the dead was a dual Chinese-Canadian citizen.