North Korean leader Kim Jong-Il arrived at a key northeastern Chinese city on the second day of a secretive trip to his impoverished state's main benefactor, a South Korean TV report said Saturday.

Kim's special train, which left Mudanjiang City in Heilongjiang Province late Friday, was seen pulling into the railway station in Changchun, capital of Jilin Province, YTN TV said.

During his last visit in August 2010, Kim had a summit with Chinese President Hu Jintao at Changchun, an economic hub. Hu urged him to open up the North's state-directed economy.

Security was tightened at the Changchun railway station and there was also a large police presence along the street from the station to a luxury hotel in the city, the reports said. Kim stayed at the hotel during his last visit.

It remains unclear whether Kim was accompanied by his youngest son and heir apparent Kim Jong-Un. The official list of Kim's 70-member entourage did not show the son's name, Yonhap news agency said, quoting a source.

Experts said the trip reflects the North's dire need for China's help and aid to ease economic difficulties and food shortages amid ongoing international sanctions over its nuclear ambitions.

His visit also shows Kim senior is firmly in charge despite his health, they said.

Kim, now 69, suffered a stroke in August 2008 and has since then been putting in place a succession plan involving Jong-Un.

The son, believed aged 27, was made a four-star general last September and given major posts in the ruling communist party to confirm his status as leader-in-waiting.

Previous trips by Kim Jong-Il to China have been shrouded in secrecy, with state-controlled media in both countries reporting them only after they end.

earlier related report
North Korean leader visiting China: reports
Seoul (AFP) May 20, 2011 - North Korean leader Kim Jong-Il travelled Friday to China, South Korean media reports said, on a trip likely focused on securing aid for his country's crumbling economy.

Kim is staying at a hotel in the northeastern city of Mudanjiang, Yonhap news agency quoted government sources as saying. The YTN and MBC television stations carried similar reports.

Earlier South Korean media reports had said the leader's youngest son and heir apparent Kim Jong-Un was making the visit, after a special train arrived early Friday in the Chinese border city of Tumen.

"It's not certain whether Kim Jong-Un accompanied his father or not," one official told Yonhap. Another source told the news agency the official list of Kim's 70-member entourage did not show the son's name.

Seoul spokespersons and China's foreign ministry declined comment.

The trip, if confirmed, would be Kim Jong-Il's third in just over a year to China, his impoverished nation's major ally and benefactor.

During the last visit in August 2010, Kim met China's President Hu Jintao in the northeastern city of Changchun. Hu urged his guest to open up the North's state-directed economy.

Kim's regime is seen as hesitant to adopt Chinese-style economic reforms for fear of loosening its grip over its people, but it faces persistent severe food shortages.

The regime is also desperate to improve living standards and revive the economy before the 100th anniversary next year of the birth of founding president Kim Il-Sung, the current leader's father.

Friday's trip reflects Kim's desire to strengthen economic ties, said Kim Yong-Hyun, an expert at Seoul's Dongguk University.

"North Korea needs China's help and aid as it strives to develop its border areas such as a free trade zone in Rason," he told AFP.

"His previous trip appears not to have been so successful. Through his trip this time, he is carrying a message that China should accelerate economic cooperation with North Korea."

Kim senior's visit also shows he is firmly in charge despite his health, professor Kim said.

Kim, now 69, suffered a stroke in August 2008 and has since then been putting in place a succession plan involving Jong-Un.

The son, believed aged 27, was made a four-star general last September and given major posts in the ruling communist party to confirm his status as leader-in-waiting.

"The trip shows North Korea badly needs assistance from China due to its worsening economic difficulties," said Yang Moo-Jin, of Seoul's University of North Korean Studies.

"China's help is crucial for the regime's survival. So Kim may seek a big deal with China to secure its economic assistance in return for denuclearisation."

Yang told AFP that Kim's health seems to be improving given his active schedule of inspection visits at home.

"I believe Kim is trying to dispel speculation about his health through his current trip."

Media reports said Jang Song-Thaek, the senior Kim's brother-in-law and one of the country's most influential men, was in Friday's delegation.

Previous trips by Kim Jong-Il to China have been shrouded in secrecy, with state-controlled media in both countries reporting them only after they end.

China's economic influence over its neighbour has grown as South Korea and Western nations cut ties amid tensions over the North's nuclear and other military programmes.

The North's trade with China rose 32 percent last year to $3.47 billion, after South Korea severed some trade ties in protest at border attacks blamed on its neighbour.