People who lost loved ones in the October 1 Lamma Island ferry tragedy criticised as "belated, insincere and involuntary" the Marine Department chief's first public apology yesterday.

One victim's relative, who requested anonymity, rejected Francis Liu Hon-por's apology, which he said was the result of political pressure.

"He had the opportunity to do this on April 30, but he didn't do so," the man said. "His apology today is not sincere, and the motive is not pure."

Liu should have apologised to the victims' families instead of to the media and Legislative Council, he said.

Liu had repeatedly refused to apologise, even after the official inquiry commission's report concluded late last month that "failings" in his department were to blame.

The man said, apart from Liu, all officials from the department appeared in the hearing, and that the former head of the department and the manufacturer of the wrecked vessel all bore responsibility.

An independent, rather than governmental, investigation into official responsibilities would be more convincing, he added.

The unnamed relative speculated that Liu changed his mind only because of widespread opposition from the public after the relatives released an open letter condemning the department.

Recalling the moment when he drafted the open letter, he said: "I couldn't sleep and I smoked heavily ... My hand was shaking when I wrote the letter because I was so angry."

A woman, whose son survived but lost his fiancée, questioned why it took her six months to hear Liu say sorry and see him bow.

"I was having a meal when I saw his apology on television. I don't quite know how I feel," she said.

"If that's a sincere apology, that would be good; but I think it is one he was compelled to do. If it's a non-voluntary one, of course I won't accept it."

While an internal investigation into who was officially responsible for the accident would now be handled by the Transport and Housing Bureau instead of Liu's department, she was unimpressed.

"It's still the same batch of people; it's still the same people investigating themselves," she said.

"At best, it's only an outer layer of the group."

Pan-democratic lawmakers agreed that Liu's apology had come too late.

The Civic Party's Dr Kenneth Chan Ka-lok said "the fact that [Liu] did not clearly explain why he procrastinated about the apology until [yesterday] gives rise to suspicion that higher-level officials or the Chief Executive had all along asked him not to make an open apology".