The bloody climax capped a 12-hour siege after the 55-year-old gunman, Rolando Mendoza, a disgruntled former police officer armed with an M-16 assault rifle, stopped the bus, which was carrying 25 people, across a wide road in Manila’s biggest park.

Mendoza was honoured by police chiefs in 1986 as one of the top 10 officers in the country. But he was dismissed in 2008 for alleged involvement in drug-related crimes and extortion, police said. He took the hostages in an attempt to demand his job back and to have his name cleared.

His body was seen slumped out of the shattered front door of the bus last night with a bullet wound to the head.

“It is most regrettable,” said Tsang who appeared close to tears during a press conference. “The way it was handled, particularly the outcome, I find is disappointing.”

Tsang said he had tried to call Philippine President Benigno Aquino but could not get through. “I hope the Philippines government can give me a full account of what happened,” he said.

Thousands in Hong Kong watched as the hostage drama unfolded live on TV.

The tour group left the city for the Philippines on Friday and was originally scheduled to arrive home last night. Their tour company, Hong Thai Travel, became aware of the unfolding drama when the tour guide made a secret phone call to the company from the back of the bus, unknown to the gunman.

“We immediately called our people there and were told the police and military had already reached there,” Hong Thai Travel general manager Susanna Lau Mei-sze said.

Twenty-two Hong Kong tourists and three Filipinos were aboard the bus when Mendoza seized the vehicle demanding he be reinstated. He released nine people during police negotiations, including two Filipinos.

As negotiations to free the remaining hostages failed, Mendoza threatened to kill the hostages.

“I shot two Chinese. I will finish them all if they do not stop,” Mendoza told Radio Mindanao Network about 10 hours into the drama. “I can see a lot of SWAT [special weapons and tactics police] coming in. I know they will kill me. They should all leave, because anytime I will do the same here.”

The Filipino driver of the bus escaped after cutting himself loose from handcuffs and screamed “Everybody is dead!” as he ran to safety.

The attempted storming of the bus after negotiations broke down turned into a debacle with commandos unable to get inside for more than an hour. They encircled the bus, smashed its windows and fired at it, but Mendoza shot back.

The crisis eventually ended when police threw tear gas inside the bus and fired again.

One woman Hong Kong survivor, whose husband was killed, demanded to know why Manila police came to their rescue so late. “It’s too late. Why were there no one to help us after so many hours?” she said at the scene of the siege. “We were in fear for so many hours. I find it really cruel.

“There were so many people on the bus - no one came to our rescue. Why?

She said her husband was killed as he tried to stop Mendoza from attacking other passengers.

“He [her husband] was brave. He rushed out trying to stop the gunman from shooting. I didn’t know whether the gunman was dead or not, but there had been non-stop gunshots.”

Last night, she was looking for her three sons who were also on the bus, aged 14, 18, and 21, and whose conditions was not known.

“I really wanted to hold my husband and die with him, but I thought of the children. So I have to protect myself.”

Aquino expressed condolences to the relatives of those killed.

“With the rest of the Filipino people, I wish to offer our deepest condolences to the families of the victims whose lives were lost in the hostage situation,” he said.

The tactics of the police in not killing the gunman early in the drama were questioned after a photo of the gunman in full view in the open doorway of the bus became public.

In Hong Kong, resident Kevin Chan said: “It’s a tragedy and a farce. Why did it take them so long to get into the bus? They’re not well disciplined and trained. Are they crazy?”

City University criminologist Dennis Wong Sing-wing said if the drama had occurred in the United States or on the mainland, the gunman would have been killed much earlier.

“It may be due to cultural differences. Filipinos are more easygoing and peace-loving so that they tend not to adopt fierce action. If the same scenario happened in the US or China, snipers would have killed the gunman a long time ago,” Wong said.

“The negotiators might also have failed to assess the situation correctly, thinking it could be solved without force, as the gunman released a number of hostages.”

Lawmaker James To Kun-sun said police seemed “a little slow” in breaking into the vehicle. Another lawmaker, Wong Yuk-man, said: “The Filipino police’s approach to the incident might be problematic. But the situation changed very suddenly. It may have been a shock for even the police, who were asked to kill.” The Hong Kong government has issued a black travel alert, warning against travel to the Philippines. Travel agents in the city will cancel all tours to Manila until further notice.

Additional reporting by Reuters, Agence France-Presse