* Blast outside exit at Urumqi train station, no word on cause
* Incident happened as President Xi wrapping up Xinjiang tour
* Xinjiang scene of growing unrest and violence (Adds comment from main exile Uighur group, background)
By Ben Blanchard
BEIJING, April 30 (Reuters) - An explosion hit a railway station in the capital of China's far western region of Xinjiang on Wednesday injuring several people shortly after President Xi Jinping spoke of plans to fight "terrorists" during a visit to the area.
Xinjiang, resource-rich and strategically located on the borders of central Asia, has been beset for years by violence blamed by the government on Islamist militants and separatists.
Xinhua news agency said there were some casualties who had been taken to hospital after a blast at Urumqi's south railway station, but gave no details. Government and state media did not give a cause for the blast.
Xinjiang government spokesman Luo Fuyong said authorities were assessing casualty figures and the cause of the blast. He would not speculate on whether it was a militant attack.
"The situation has been brought well under control," he told Reuters by telephone. "The wounded are receiving medical attention ... Public security forces are on the scene dealing with it."
"We are deeply concerned by what has happened," Luo added.
Exiles and many rights groups say the real cause of unrest in the region is heavy-handed conduct by authorities, including curbs on Islam and the culture and language of the Muslim Uighur people who call Xinjiang home.
Dilxat Raxit, spokesman for the main Uighur exile group, the Germany-based World Uyghur Congress, said he feared the blast would lead to a new round of repression against Xinjiang's Uighurs.
"It's extremely worrying. No matter what happens, China first of all represses the Uighurs, leading to many innocent Uighurs being locked up," he said by telephone.
"We can see from this that Xinjiang is in a period of turmoil, and such incidents could happen again at any time. This is the trend and it's directly related to Beijing's policies."
Unrest in Xinjiang has led to the deaths of more than 100 people in the past year, prompting a tougher stance against Turkic-language speaking Uighurs, many of whom chafe at government controls on their culture and religion.
BLOOD AND DEBRIS
Pictures on China's Twitter-like Weibo service, which Reuters could not independently verify, showed blood on suitcases and debris on the ground in front of the station.
Another picture showed what appeared to be a small blast area near a police post, though it was unclear if there were any casualties in the photograph.
Many of posts carrying these pictures were quickly removed by censors, as often happens in China.
Xinhua said the blast was centred around luggage left on the ground between an exit and a bus stop. The station re-opened at 9pm (1300GMT), some two hours after the blast, under a heavy police presence, it added.
Urumqi was the scene of deadly ethnic riots in 2009, with nearly 200 people killed when Uighurs clashed with members of the majority ethnic Han Chinese community. It has been relatively calm since.
It was not clear if President Xi was still in Xinjiang at the time of the blast at the end of his four-day visit to the region in which he stressed tough policing to fight "terrorists".
"The long-term stability of Xinjiang is vital to the whole country's reform, development and stability; to the country's unity, ethnic harmony and national security as well as to the great revival of the Chinese nation," Xinhua quoted Xi as saying during his visit, in a report on Wednesday.
China's nervousness about militancy, especially Islamic militancy, has grown since a car burst into flames on the edge of Beijing's Tiananmen Square in October, and 29 people were stabbed to death last month in the southwestern city of Kunming.
The government said Xinjiang militants were responsible for both incidents.
Uighurs have traditionally followed a moderate form of Islam but many have begun adopting practices more commonly seen in Saudi Arabia or Afghanistan, such as full-face veils for women, as China has intensified a security crackdown in recent years.
While China reacted to the 2009 riots by pumping money into less-developed southern Xinjiang, in an implicit recognition of the economic causes of the unrest, it has taken a much harsher line of late, especially towards dissenting voices.
The government detained lham Tohti, a Beijing economics professor who has championed Uighur rights, in January and subsequently charged him with separatism.
Advocates for Tohti say he has challenged the government's version of several incidents involving Uighurs, including the car fire on the edge of Tiananmen Square. (Editing by Robert Birsel)