The United States conducting frequent and large-scale reconnaissance missions in the South China Sea is the root cause of accidents between US and Chinese militaries, experts said.

Therefore, China and US militaries should enhance communication and strengthen mutual trust to nip potential accidents in the bud, they added.

A US Navy plane approached a Chinese military aircraft on Wednesday in the airspace near Huangyan Island, one of China’s islands in the South China Sea, an official close to China’s Defense Ministry said on Friday. The Chinese plane, which was conducting routine training in the region, reacted professionally and adhered to law.

“We hope the US will take the big picture of Sino-US military relations into account, and take practical measures to remove the root cause of accidents between the two countries in air and on sea,” the official added.

This was the first time US and Chinese military planes met in 2017. The last two incidents were on May 17 and June 7. A US official told Reuters that the incident was rare and inadvertent.

Ma Gang, a professor from the People’s Liberation Army National Defense University, said the US has been conducting frequent and large-scale reconnaissance missions in the South China Sea for decades, and “this is the root cause for the accidents.”

“If the US still views China as an obstacle, then similar accidents are still likely to occur,” he said. “Accident prevention requires the US to keep an open mind about China and remain honest in dialogue.”

The US government will remain committed to the one-China policy, and develop “a constructive relationship that benefits both the US and China,” according to a White House news release on US President Donald Trump’s first phone call with his Chinese counterpart Xi Jinping on Thursday, which described the call as “extremely cordial”

Last week, US Defense Secretary James Mattis suggested that diplomacy should be the priority in the South China Sea, and the US saw no need for “dramatic military moves” at this time.

Fu Mengzi, the vice-president of the China Institutes of Contemporary International Relations, said it is a good sign that China and the US are having positive interactions, and the US should build mutual trust and respect China’s stance on principle issues like national sovereignty and territorial integrity.

After being held in India for 54 years, Chinese veteran Wang Qi was ready to make his long-awaited trip back home on Saturday.

According to the Chinese embassy in India, 77-year-old Wang had left his home in central India’s Madhya Pradesh and arrived in New Delhi on Friday afternoon.

He was eager to return to hometown in Shaanxi province and would start the journey as early as Saturday, said the embassy.

In 1963, Wang, a Chinese army surveyor, got lost, crossed the border and was captured by Indian authorities. He was moved from one jail to another for nearly seven years

When he was finally released in 1969, police escorted him to the remote village of Tirodi in Madhya Pradesh and told him to start a life there. He married a local woman, and they had three children and grandchildren.

Foreign Ministry spokesman Lu Kang said on Monday that China had been “pushing India” to complete procedures to return the veteran. In 2013, the Chinese embassy in India issued him a 10-year Chinese passport and a living allowance every year since then, Lu said.

Vikas Swarup, the Indian External Affairs Ministry’s spokesman, said on Thursday, “The ministry is helping Wang and his family members－including his son Vishnu Wang, daughter Anita Wankhede, daughter-in-law Neha Wang and grandson Khanak Wang－to visit China to meet his extended family.”

“We are working with the Chinese embassy in Delhi and the Indian embassy in Beijing to ensure that all formalities are completed and arrangements are in place,” he said.

A China Central Television report on Friday said that Wang is eager to taste noodles, a local specialty in Shaanxi, after arriving home.

Wang’s plight was highlighted last month in a special report by the BBC.

On Feb 4, Luo Zhaohui, China’s ambassador to India, spoke by telephone with Wang and expressed sympathy over his suffering over the years. Yan Xiaoce, a counselor at the Chinese embassy in India, visited Wang’s village on the same day, according to the embassy.

Liu Shurong, another Chinese veteran, underwent the same plight as Wang and lives in the same village. But Liu said he had no intention to return to China because he no longer has family there, the embassy said.

A fire broke out on Friday inside a Hong Kong underground train near a busy station, with at least 17 people being injured and a man being detained after claiming that he has set fire with a Molotov cocktail.

The fire broke out at around 7:00 local time inside an underground train crossing the Vitoria Harbor for the busy Tsim Sha Tsui station, forcing the train to stop at the station and all the passengers to be evacuated, public broadcaster RTHK reported.

Footages from social media show flame and smoke from inside the train and several people burned.

The injured, two of whom in severe condition, were sent to nearby hospitals.

A man at the age of around 60 claimed that he set the fire with a Molotov cocktail. The police has detained the man and has been investigating his motive,a police officer told media outside the station, which has been temporarily closed.

The counter-terrorism response unit has been deployed at the scene.