Family members of the 23 mainland tourists and a tour guide killed in a bus fire in Taiwan will arrive in Taipei on Thursday, as authorities on both sides of the Straits work together to handle the accident aftermath.

A chartered flight of China Southern Airlines with more than 90 people expected on board will leave Dalian, Liaoning province, where most of the victims were from, at about 1:15 pm on Thursday and arrive in Taipei at 4:10 pm, according to the airline.

The Taiwan authority has requested that contact points be set up to receive the victims' family members, provide transportation and prepare documents informing them of their rights.

"We hope to provide the family members and relatives as much clarification on what caused the accident, while providing them with the support they need," said Lin Chuan, chief of Taiwan's executive body.

"At the same time, information needs to be transparent ... to ensure that everybody feels that this is being handled properly."

Twenty-six people, including 23 tourists and a tour guide from the Chinese mainland and two people from Taiwan - the driver and a tour guide - were killed when the tour bus crashed into a barrier on a highway and caught fire near Taiwan Taoyuan International Airport on Tuesday.

It was the deadliest incident involving mainland tourists in Taiwan since the island opened up to mainland travelers in 2008.

Premier Li Keqiang has ordered the appropriate mainland authorities to look into the accident as soon as possible and to properly deal with follow-up matters, according to the Taiwan Affairs Office of the State Council.

"We are deeply sad for the victims of the accident," the office said in a statement on Wednesday. "Taiwan authorities should identify the cause as soon as possible, properly deal with follow-up matters, protect the interests of victims, strengthen safety management, eliminate potential problems and protect tourists to Taiwan."

Nine mainland officials, including a director-level official from the Association for Relations Across the Taiwan Straits, arrived in Taipei on Wednesday. They will assist relatives in making arrangements but will not be involved in negotiations regarding compensation, according to the Taiwan Affairs Office.

Local media in Taiwan reported that each victim's family could get compensation of about 1.12 million yuan ($168,000).

On Wednesday, Taiwan authorities ordered some tour buses off the road after questions arose about why emergency doors and windows of the bus involved in the accident did not open.

A preliminary investigation found that the handles of the emergency doors might have been impaired by the heat from the inferno inside the bus, according to China Times.

Investigators believed a mechanical or electrical failure near the driver's seat might have led to the accident, media reports said.

But prosecutors in Taoyuan district said further investigation was needed to determine the cause of the accident.

China Post and AFP contributed to this story.