A Chinese mainland spokesperson on Saturday denounced a tour bus arson that killed 24 mainland tourists in Taiwan in July, after Taiwan authorities confirmed the driver's drunk-driving, arson and murder.

"We strongly condemn the deliberate vicious criminal case, and express strong indignation over such heartless, inhuman conduct," said a spokesperson of the State Council Taiwan Affairs Office.

Since the incident took place on July 19, the office has repeatedly urged Taiwan authorities concerned to investigate the cause of the incident and responsibility, and give an explanation to the families of the victims, said the spokesperson, adding the incident and some hurtful words and deeds from the island have had a serious impact on mainland tourists' traveling to Taiwan.

Next, mainland authorities concerned will continue to urge the Taiwan side to well handle the follow-up issues, including compensation, and will provide full assistance to the victims' families in handling related affairs, said the spokesperson.

The Taiwan driver of the tour bus was drunk, set fire and splashed gasoline on himself and passengers, killing himself, a local tour guide, and 24 tourists from the mainland, Taiwan prosecutors said.