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By Aweys Yusuf

MOGADISHU, Nov 13 (Reuters) - Somali government forces battling Islamist-led insurgents ordered two more radio stations off the air on Tuesday, as a U.N. envoy said the latest fighting made the country's humanitarian crisis the worst in Africa.

Authorities in the turbulent nation have often accused local broadcasters of backing the rebels. On Monday they shut down Shabelle Radio for the eighth time this year. Then on Tuesday, heavily armed troops raided Simba Radio and Radio Banadir.

"They terrorised the employees ... All the reporters panicked and ran when they saw the guns," Radio Banadir's deputy director, Ali Muhamed Aden, told Reuters.

Mustafa Haji, the chief editor at Simba Radio, said an officer told him the order taking them off the air would apply to all independent stations in the capital Mogadishu.

Rampant insecurity keeps most foreign correspondents out of Somalia, so locals are left to report on an insurgency that is targeting the interim government and its Ethiopian allies.

Speaking after meeting aid workers in neighbouring Kenya, the U.N. special envoy to Somalia, Ahmedou Ould Abdallah, said he could see no reason to close a radio or newspaper.

"They (the media) are helping people to help themselves. I think it is something to be avoided at all costs," he said.

The latest effort by Ethiopian forces to crush the rebels in Mogadishu has triggered fighting that has killed at least 70 people. The U.N. refugee agency UNHCR says some 173,000 residents have fled their homes in the last fortnight alone.

"WORST IN AFRICA"

Nearly half-a-million civilians have been forced out of the city since February by repeated rounds of violence, and Abdallah said the country's humanitarian crisis was now "the worst in Africa", including Darfur.

"It has been like that since the start of the year, and the fighting of recent days has only made it worse," he said.

Nearly 90,000 of the recently uprooted have fled to Afgoye, a town on the southwestern outskirts of the capital.

A UNHCR spokesman in Geneva said the needs in Afgoye were immense: "People can no longer find space for shelter around the town itself. Many families are simply living under trees."

Abdallah, the U.N. envoy, called on Somali President Abdullahi Yusuf to ensure a new prime minister would help "open up the system to people who do not agree, to be more inclusive".

Former Premier Ali Mohamed Gedi resigned last month after months of feuding with Yusuf. His successor is yet to be named.

The Somali president gave no clues during a visit to Nairobi on Tuesday, but said reports that Gedi was trying to re-open talks between them rang hollow.

"If he is proposing any dialogue now, why didn't he do it during his three years in office? It doesn't have credibility."

Yusuf told reporters he would talk to any Somali or Somali group not designated as terrorists, including members of an opposition alliance founded in September in Asmara, Eritrea.

"If they still want to solve this through political means, we are still willing to talk to them," he said.

He blamed the latest fighting on groups wanting to "score political points", and called on residents to resist them.

"They could become vigilantes, they could confront it." (Additional reporting by Andrew Cawthorne and Bryson Hull in Nairobi and Stephanie Nebehay in Geneva; Writing by Daniel Wallis; Editing by Giles Elgood)

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