Relatives of the injured and killed Chinese nationals in the bombing attack in Bangkok have arrived in the city, the Chinese embassy in Thailand said.

Seven Chinese were killed and 24 others injured in the deadly bombing that ripped through the Erawan Shrine in downtown Bangkok Monday morning, which left 20 dead and more than 120 others wounded.

Relatives of all seven deceased Chinese had arrived in Bangkok by Thursday noon, the embassy said.

Families and relatives of those injured visited their loved ones in hospitals upon arrival, an embassy official told Xinhua.

The embassy has been in close contact with the Thai government for treatment of those injured Chinese and went into details for compensations for the Chinese victims in the bombing, he said.

Thai Prime Minister Prayut Chan-o-cha on Tuesday vowed to expedite all investigative efforts to find the perpetrators of the explosion and bring them to justice.

"From this incident, it is apparent that there are active individuals or groups that harbor the intention to damage Thailand, who may be pursuing political gain or other intentions by damaging the economy and tourism," Prayut said.

Experts believed the impact of the explosion on the tourism sector is " immediate."

"It is a soft sector. When you have this kind of scare tactic, you'll have cancellations of tours, a lot of reconsideration and reviews of travel advisories, so the impact is immediate," said associate professor Thitinan Pongsudhirak at the Bangkok-based Chulalongkorn University.

In a statement on Tuesday, the United Nations World Tourism Organization (UNWTO) strongly condemned the attack.

"On behalf of the global tourism community, UNWTO offers its heartfelt condolences to the families and friends of the victims," the statement said in apparent recognition of its impact on the country's tourism.

Security concerns and its potential implications would add more pressures to Thailand's economy, Thitinan said.

"The economy is already in the doldrums and growth forecast has been revised downwards. The government is already seen as lackluster on the economy. The economy is underperforming, so the military government will be under more pressure to deliver," he said.

Thailand's new cabinet line-up was unveiled Thursday, with Somkid Jatusripitak replacing Pridiyathorn Devakula as the deputy premier in charge of economic affairs.

"The cabinet reshuffle is not going to help that much. It is of marginal significance," Thitinan said.

As for the perpetrators of the bomb blast, Thitinan underscored that at this stage, all possibilities have to be entertained, but evidence is needed in any scenario.

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