Mystery still surrounds the whereabouts of a Chinese national who disappeared after scaling Mt Kilimanjaro last month.

Tanzania National Parks (Tanapa) officials and Kilimanjaro regional authorities told The Citizen at the weekend that they were still searching for the tourist who was accompanied by several other Chinese climbers on an expedition to climb Africa's highest mountain.

Tanapa public relations officer Pascal Shelutete said they could not speculate on what might have happened to Mr Zhang Shaosheng, who was last seen on July 17.

He said Mr Zhang disappeared as he was descending Mt Kilimanjaro, having successfully scaled the mountain along with other tourists. A rescue mission had been underway since Mr Zhang went missing, Mr Shelutete said, adding that rescuers were combing the mountain's higher reaches at the weekend.

"We are looking for him in the area he was last seen it's an area that is devoid of dangerous wild animals due to the high altitude," he said, and disputed earlier reports that Mr Zhang had used the Machame route. Mr Zhang climbed the mountain through the famous Marangu route, the Tanapa official said.

Mr Shelutete added that it was "very rare" for climbers to be lost without trace at the mountain, adding that a cash reward was being offered to anybody who had any information that could help rescuers locate Mr Zhang, whether dead or alive.

Such information should be forwarded to the Chinese Embassy in Dar es Salaam, the police or Kilimanjaro National Park (Kinapa) authorities.

Kilimanjaro regional police chief Lucas Ng'hoboko confirmed that a search was on, but declined to give further details.

"We have been notified of the missing Chinese national. Police and national park officials are still looking for him in a joint operation. I have no further information to give you," he said.

Mr Shelutete said deaths of climbers had been reported on the mountain in the past, but added that the bodies of those who died were invariably found.

"This is a rather rare and mysterious case. If he has died, then we were supposed to have found his body by now," he said, adding that Tanapa would issue an official statement today.

The Chinese news agency Xinhua reported last week that Mr Zhang, an amateur mountaineer from China's Guangdong province, went missing as he was descending the 5,895-metre high mountain last month.

It said Kinapa authorities had since organised three groups of rescuers assisted by two light aircraft to search for the missing person.

The route that Mr Zhang took to the top of the mountain has been the subject of controversy with some sources saying that he climbed via the Machame route to the northwest of the mountain.

But Tanapa officials maintain that he used the Marangu route, which is favoured by most climbers.

After taking pictures on the Uhuru Peak, the Chinese climbers reportedly started their descent, during which Mr Zhang went missing between the summit and the Barafu Camp, located at an altitude of 4,600 metres above sea level.

China's ambassador to Tanzania, Mr Liu Xinsheng, and Mr Zhang's wife, Zeng Wei, last Wednesday issued a joint request for information on the disappearance.

Mr Zhang, in his early 40s, and was wearing a bright-coloured heavy jacket and a pair of glasses and was carrying two cameras at the time of his disappearance. He has black eyes and black hair.

Mr Zhang's wife and the Chinese embassy in Dar es Salaam have distributed leaflets with colour pictures of the missing person and basic descriptions of him. The leaflets are in English and Kiswahili.

Ms Zheng requested climbers from Tanzania and overseas who went up or down the Marangu route on July 17 to try to recall whether they had met a lone Chinese climber.

The last major tragedy on Mt Kilimanjaro involving foreign tourists took place on January 4, 2006 when three American climbers died after being hit by falling rocks and boulders. They were identified as Christian Fero, Mary Lou and Betty Orrick.