One of China’s largest tour operators has suspended cooperation with Malaysia Airlines and said it will cancel existing flight arrangements with the carrier.

"Considering the fact that a succession of accidents have involved Malaysia Airlines recently, and that Chinese tourists have concerns over the carrier’s safety record, we must fulfill our responsibility of ensuring the security of our fellow citizens," Beijing-based China Youth Travel Service said in a statement on Wednesday.

New bookings will be suspended and existing itineraries that include Malaysia Airlines will be changed to other carriers, it said.

The agency also promised full refunds to consumers who want to cancel trips that would have used the Malaysian carrier.

Another large travel agency, China International Travel Service Head Office, has seen a sharp decline in consumers signing up for tours to Malaysia, according to its publicity officer, Meng Qingfu.

Malaysia Airlines Flight MH370, which shuttled large numbers of Chinese tourists between Kuala Lumpur and Beijing, has been missing for nearly three weeks.

Malaysian Prime Minister Najib Razak announced on Monday that the aircraft crashed into the southern Indian Ocean and that there were no survivors. But an international search operation continues to race to find the missing Boeing 777.

Adding to the jitters about travel to Malaysia, another aircraft, Malaysia Airlines Flight MH066 from Kuala Lumpur to Incheon, South Korea, was diverted to Hong Kong International Airport early on Monday because of a mechanical problem involving an inoperative electrical generator.

The company said that electrical power continued to be supplied by the Airbus A330-300’s auxiliary power unit.

The MH370 incident has cast a giant shadow over the Chinese public’s sentiment about travel to Malaysia, with nearly 80 percent of respondents in an online poll saying they will not go to the Southeast Asian nation in the near future.

The poll, which was conducted by Sina.com, one of China’s most popular news portals, surveyed nearly 60,000 Internet users by late Wednesday. Only 18 percent of respondents said they would not exclude Malaysia when choosing destinations.

Most netizens who made comments after taking part in the poll said the tragedy of losing more than 239 people, most of them Chinese, as well as the "awkward measures" taken by Malaysian authorities in dealing with the incident, make them want to avoid travel there.

Eleven Chinese travel agents told Reuters that bookings between China and Malaysia had fallen sharply and that many people have canceled trips already booked.

"We used to have 30 to 40 customers a month for group tours to Singapore, Malaysia and Thailand. Now there is no one asking about this route or booking," a travel agent surnamed Chen told Reuters. Chen is with Comfort Travel in the southern city of Guangzhou, which focuses heavily on Southeast Asia tours.

An outbound tour manager with an agency in Jiangsu province, who declined to be named, said: "Now the biggest concern of our tourists to Southeast Asia is whether they will fly on Malaysia Airlines. Some consumers even are willing to pay more money to book other airlines rather than going with the cheaper tickets offered by Malaysia Airlines."

Malaysia was among the top 10 overseas destinations for Chinese tourists in the past several years. In 2013, nearly 1.8 million people from China traveled to the Southeast Asian nation — a 14.9 percent increase from 2012.

The Malaysia Tourism Promotion Board said China was Malaysia’s third-largest tourist market last year, behind Singapore and Indonesia, and it had expected 2 million Chinese visitors this year before the MH370 incident.

Malaysian Tourism and Culture Minister Mohamed Nazri Abdul Aziz said on Monday that "Visit Malaysia Year" promotions in China would be halted until the MH370 case is closed.